I've been around the top of the BGA leaderboard for this game. It's mostly about being Witch, buying PoPs in round 1, and trying to grab Reanimate. BGA players taught me that the game contained even less slack than I thought by opening with round 1 turn 1 alchemize, round 1 turn 2 buy alchemist's tower, which I eventually adopted.
It feels like a lot of the variety in the game should come from the 8 cards in your deck, but it can't if you just discard them most of the time.
OK! Well, I guess it comes down to what you mean by "completely collapse". I enjoy the BGA leaderboards, but only got to the top 50 or so when I was actively trying.
I agree that you're going to discard 3/4 of your artifacts, and ~50% of them are almost never worth playing. But I've been continuously surprised by people pulling out wins with PoP/artifact combinations I didn't expect to be viable.
If your definition of "completely collapses" is "some paths are much better than others in high level play", then I guess we just disagree on what makes a good heavy board game.
I do agree with you that Wingspan has a corvidae problem, though; I've never seen anyone but a beginner lose with an early raven.
From my PoV it's not "some paths are much better than others" so much as "almost all of the paths are not worth taking." The game feels really centralized around the 3 best PoPs and some Athanor/Philosopher's Stone gameplans (though other stuff can win and it's always fun to see that). I can't call any mages *blank* in the same way I can call some Roll starting devs blank, but your Druid is just not expected to have a great time against a Witch or Duelist or even a Seer.
This is all subjective, of course. The Splendor designers obviously intended for players who purchase a large number of small holdings to be able to win. Every variant in the expansion works to address this issue. Another player could reasonably say "Splendor has failed because everyone just rushes to buy about 2 big holdings." To me, "Splendor but everyone goes for big holdings right away" is still pretty good at being Splendor. "Res Arcana but you rush a PoP and get like 8 VPs from it and 2 from a monument" feels disappointing compared to the game I thought I would be playing. I'm glad you like it! A friend tells me the 2nd expansion makes a lot of things better, so I'm looking forward to trying it out.
It feels like a lot of the variety in the game should come from the 8 cards in your deck, but it can't if you just discard them most of the time.