It's super fun to be living in an era during which data is almost always trumped by narrative and "beliefs". So, the Big 10 sucks because it is 1-7 in the National Title game since the dawn of the new millennium, and as you say that doesn't happen by accident.
I think that in my lifetime only IU, MSU and Michigan have cracked the code to winning the NCAA Tournament, and they've each only done it once since the field expanded to 64 back in 1985. So, that's just 3 Titles in 37 tournament. By your reckoning the Big 10 has always sucked, so why make such a big deal about it now?
The crazy thing is that if the Big 10 had snuck a couple more teams in the Sweet 16 this weekend, many would be saying "Wow, look at how good the Big Ten is".
The Big 10 wasn't great this year, but you didn't have to wait until today to know that. The conference didn't receive a #1 or #2 seed. The buzzsaw Hawkeyes, the hottest team in the land, only got a #5 seed after winning 12 of their last 14 and a BTT Championship.
It seems to me that the conference has done just fine in the 2022 tourney. Nothing great accomplished yet, but pretty much just as might be expected based on seeding. There are still games to be played, and thus far only the ACC has had a decidedly better performance. By late Friday night we'll know more.
Also, at the beginning of the season, only Purdue and Michigan were ranked in the Top 10 and here they are playing for the right to go to the Elite Eight. Illinois was ranked #11 and got bumped off by #15 Houston. OSU was #18 and lost to #4 Villanova. Iowa, MSU, Wisconsin, Rutgers and IU were all perceived to be outside the Top 25 before we ever tipped off the season. All in all the Big 10 just went according to Hoyle so far. Hard to spin it as an agitating underachievement for the conference imo.