Long post warning, but this is not something that can be explained in a few lines. Anyone who says otherwise doesn't know as much as they think they do.
Ok, so EGR & DPF are different things, doing different jobs. The emissions update can affect longevity of either but in different ways. Between some correspondence of my own with VAG in Ireland, and reading through papers from UK parliament on the matter, two things were established about the update:
Increased use of EGR to directly control NOx formation during the combustion process
Increased soot generation to allow passive reduction of NOx by oxidising soot held in the DPF
Some background on how/why this is so. NOx forms during the combustion process due to the 'burning' of atmospheric nitrogen that has been brought into the engine. The temperature and pressure present during combustion create suitable conditions for this to happen. Nitrogen and fuel are competing for oxygen during combustion.
In engines that run rich (more fuel than the available oxygen can consume), NOx generation is minimal as oxygen will more readily react with fuel rather than nitrogen. But this is not desirable for economy or other criterion pollutants. Also, in diesel engines, running rich makes them run hot which is undesirable as well.
Engines that run lean are more economical but the excess of oxygen present means conditions favour production of more NOx. DIesels have always had this problem as diesel engines are happier running lean. Modern DI petrol engines which support lean running are also vulnerable to increased NOx generation.
One other aspect of combustion behaviour is that regardless of how much oxygen is present, a certain gas volume is needed to ensure adequate distribution of fuel droplets and vapour so that combustion can initiate. Too close is bad as the concentration of fuel vapour between droplets won't get down below the Upper Flammability Limit and combustion won't initiate or propagate.
EGR helps solve this conundrum. Exhaust gas is much lower in oxygen than fresh air obviously, making it relatively inert from a combustion perspective. The trick with EGR is that it uses this inert exhaust gas to displace some fresh air from the combustion process, so now there's less excess oxygen available to form NOx, but it maintains the same gas volume in the cylinder, so there's still enough distribution of fuel in there to allow the combustion process to proceed.
It generally only operates at low engine loads where fuel requirement is minimal and there would otherwise be a lot of excess oxygen in the cylinder. When the load ramps up and fuel/air ratio approaches stoichiometric, EGR would cause more problems than it solves.
The emissions update increases EGR under low-moderate loads, which is what most of the EU test cycle is run at, but probably has changed very little at higher loads. The reason some EGRs are dying after it is that they have gotten gunked up over the life of the vehicle prior to the update, but only outside of the range of movement they would have operated within. The update commanding wider EGR opening means pushing the valve into that gunk and some of them get stuck and fail. Once replaced, a similar failure in future is unlikely, beyond the normal life expectancy of the component, as any subsequent gunking will be outside the new range of movement.
Now DPF. Its job is pretty self-explanatory. All DI engines (petrol or diesel) produce soot, it's an inevitable side effect of spray combustion processes. Diesels have been DI for much longer than petrols, and have until recently received the lion's share of attention when it comes to reducing/eliminating particulate emissions. (Euro 6 has brought in a requirement for particulate filters on petrols.) DPFs are a filter matrix designed to capture soot from the exhaust and hold it until a predetermined amount is stored at which point the engine shifts its operating parameters and ignites the soot to clear the filter. A small amount of ash (mostly from lubricating oil that's made it into the exhaust) gets left behind, and this eventually kills the DPF but it takes a while.
Now NOx comes back into the picture. Nitrous oxides are themselves pretty decent oxidisers, as evidenced by their use in a lot of rocket motors for that purpose (a bit easier to handle than liquid oxygen). Even with EGR and other combustion management strategies to minimise NOx generation during combustion, there's still some amount of it generated and this needs to be dealt with. One strategy employed to deal with this is set up the DPF so that the NOx passing through it in the exhaust gas stream oxidises some of the soot collected in it, turning it into CO2 and nitrogen. This process passively regenerates the DPF also, eliminating soot during normal engine operation. Which is what most EA189 engines in Skodas do.
The emissions update increased soot generation to use it as a NOx reduction measure in the DPF. It's not going to affect the amount of oil ash getting into the filter. The only way it might shorten the DPF life is due to the more frequent regens resulting in more thermal cycling, causing a failure of the filter material itself. This is more likely to be on cars that are driven on lots of short trips. Longer trips result in a lot more passive regeneration and thus fewer active regeneration cycles.
Could one affect the other? Yes, they're part of the same system. The whole thing has been engineered to work together as well as possible, while trying to make the best of the inevitable compromises a complex engineered system requires. It's not as simple as your mate down the pub might have you believe though.
To backtrack a little, the engine ECU is monitoring and controlling two core parameters: how much fuel goes in, and how much air goes in. How much air goes in is monitored by the MAF and MAP sensors. How much fuel goes in is monitored by the fuel metering system. But there's a third part to this that never gets discussed but that is nevertheless important: the lambda sensor in the exhaust. That one monitors how much oxygen remains in the exhaust leaving the engine and that data is used to control the quantity of fuel injected into the engine (in tandem with the MAF/MAP readings).
Why does this matter? From descriptions I'm seeing on this thread, the EGR emulators are just tweaking the MAF readings, making the engine think EGR is working normally. If we follow this through, the engine is now getting more oxygen than it realises, meaning more oxygen in the exhaust. The lambda sensor sees this and tells the engine to send more fuel. During high EGR demand driving situations this means more fuel, higher fuel consumption, maybe a bit more soot, maybe more NOx. I don't know if the ECU is set up to detect mismatch between fuel injection quantity and MAF, if it did, you could see errors down the line (I'm guessing a bit here TBH).
Personally, I don't think EGR defeats like this are a good idea. On modern engines with such closely coupled sub-systems running within tight margins, it's too easy to upset something without realising it until bits start to break. If you're willing to accept that possibility, feel free to go for it. You are ultimately your own warranty though: the manufacturer will not want to know about it if things break. There's always the possibility of it ultimately costing more to put right than if it had been fixed day one.