I think what is really hard to perceive is that 90% critical avoidance is in reality an extremely big damage mitigation in the long run but we as players don’t see it that way. When we think of critical strike avoidance, we want to protect for that off chance we get that random 1 huge hit that can potentially kill us and if we don’t have 100% critical avoidance, we don’t really feel protected. Then when we die with 99% critical avoidance, it’s easy to blame that 1% for why we died (I know I would haha). When I play hardcore, I also struggle with this perception, it is hard for me to switch over all my high HP gear or off of Wolven flesh unless I can fully switch over to 100% critical avoidance to fully compensate, even knowing how it works fully.
Critical strike avoidance is a strong stat, and I agree for hardcore, it’s a strong primary defensive stat to go for as an endgame additional defensive layer. I don’t find that particular a bad thing or that qualifies it as “unfair”; it’s just like capping resists and armor or dodge to build other defensive layers. There are also many ways now to cap this defensive stat that allow it to not be so gear taxing from blessings, exalted mods, legendaries and sealed affixes which provide a fair amount of gear flexibility.
“Critical Damage Mitigation”, I do like this better than Critical Strike Avoidance. Critical Strike Avoidance can be misleading, it sounds more like a dodge when you are with 100% Critical Strike Avoidance just removing all the bonus damage taken from the critical strike reducing it back to a normal hit.