Things have changed a lot in the past decade or so, and they're never going back to the way there were.
Mid-majors are crucified for losing Q3/Q4 games, which unfortunately will happen even if you're a good team. Meanwhile, it's much harder to get quality home games if you're UB, Bona or Murray State, etc. Not too long ago Buffalo hosted UConn and Bona hosted Miss State. That ain't happening again, unless you want a low level P5 at home.
The powers know they don't need to schedule a ton of quality OOC games as virtually their entire conference schedule is filled with good games, and they sure as hell aren't going on the road to a mid-major unless the team is amazing (Q1).
With conferences likely going to 20 game conference slates, it'll be even harder to schedule going forward.
We are living in an age where a P5 can get an at large with 15 + losses...AND STILL AVOID DAYTON!
To your point, while it IS possible to get an at large out of the MAC, it is very, very difficult and is only getting harder. You have to be virtually perfect and probably win 30 games with maybe one or two bad losses.
I try to tell this to Bonnies fans, but your Q3/Q4 games don't matter...unless you lose. When Bona was rolling through a crappy A10 in 2018, people thought we were a lock after being URI. Unfortunately, that was not true. If we had loss one more game the rest of the regular season, we would have been in the NIT 100%.
That's the one thing the separates bubble teams on Selection Sunday. The power bubbles rarely have bad losses, the mid majors usually do have a couple. Add in the fact that mid majors usually get most of the quality games away from home and it makes things so much more difficult to compete for at larges.
Sorry for the rant!