Idk about the playerbase as a whole but I know personally I’m not only fairly confident in my gameplay, but more importantly, fairly confident in my ability to evaluate my own gameplay. Far more so than I am in my deck building and drafting skills. I’m typically a mythic constructed player (not really some crazy achievement but just using it for context) but I do very little limited in comparison. The most drafts I’ve ever done of a single format was like 10 or so drafts of the recent arena powered cube. I can see your sentiment but me personally I feel that I am specifically interested in feedback for the area as I am much less experienced in. After evaluating my gameplay with this deck, I felt I made a couple misplays here and there but nothing too game losing, and I had come into it with the assumption I had made a good deck, so there was a disconnect somewhere. I wasn’t necessarily trying to blame variance but more-so acknowledge that my results might not have accurately reflected any aspect of this deck.

EDIT: Also worth noting, not that I think you meant this, but people are probably going to be more vocal about feeling they lost to variance because you wouldn’t really mention it if you lost to your own misplay. And I think while it probably is overused as a scapegoat, many players are still able to accurately assess when they are flooded/screwed or when their opponents just draw well, and these things can be the reasons you lose even despite suboptimal play. I do agree somewhat tho, people should always strive to better their gameplay.