How do you even define progression points? Like, let's take P2S for example. There's a mechanic that most people are referring to as "Limit Cut" (which isn't its actual name, thanks PF...) that tends to be the biggest wall in the fight. How do you define whether or not someone's progressed past Limit Cut?

Have you progressed past Limit Cut if you're a PLD who popped Hallowed Ground and stood off to the side while the entire rest of the party ran around like headless chickens and got deleted?

Have you progressed past Limit Cut if most of the party died to it but there was a SMN still up who raised a healer who LB3'd and the party made it to enrage on that pull?

Likewise, have you not progressed past Limit Cut if you were slightly out of position and got clipped by something and killed while the rest of the party survived because all 8 people involved know the strat and were (roughly) in the right spots?

Progression is a very vague concept. We want it to mean "I understand every mechanic prior to X point in the fight and am capable of consistently executing all of them correctly." But there isn't really a way to define that in terms the game would understand without introducing other room for error. Even "first death = that's the prog point for the whole party" fails when someone derps on an early mechanic and the party hits enrage with only that death, because the party most certainly has progressed past that early mechanic.

I can tell you from experience that PF Hell is a real place and it sucks, and I definitely agree with you that having some better way to filter people than just listing your prog point in the description and praying you get 7 people at or after that point would be a massive help, but I just don't see it being feasible.