My take is simply Buyer beware. Some online companies guarantee fresh build dates others do not. My impression is that Avon have always been a budget tyre that has the added bonus of ultra fast wear.
Cracking like that shown is common across many makes, one reason I gave up on Michelin. Apparently partly down to low useage and stood outside exposed to the elements and UV. Low mileage users who don't move their car often, the oils in the compound don't get exercised and the surfaces dry out and cracking occurs. But that typical example is not a safety issue, simply a cosmetic one, that part is not on contact with road after all.
No perfect tyre, all a collection of compromises, this months batch may be different from last months depending who mixed the ingredients. In the past I stuck to Continental Premium Contacts for my Alhambra as no alternatives were available on my size, each set was different, made in Portugal, Spain, Hungary 8mm, 7mm
Several years ago I bought a used spare wheel/tyre from ebay for our fabia. Fitted with an old BF Goodrich G grip tyre (49/09) Pressed into use many times over the years, currently fitted on our remaining fabia, its been quite a remarkable tyre, low wear, no sign of the cracking I regularly saw on Michelins, or borderline delamination on every Goodyear Efficient Grip performance when worn. Tyre walls still look like new, no deterioration apparent. Tyre was made in Poland, BF Goodrich is owned by Michelin.