I think estimating Final Fours is kind of dumb or impossible. Getting there only takes 4 games. This means relatively bad teams can make it, and relatively good teams can fail to make it.
If you actually look at Purdue’s Final Four odds objectively according to the analytics, their odds of making it this year were about 22% (90% chance to beat Yale, 53% chance to beat Texas, 85% chance to beat St. Peter’s, 54% chance to beat North Carolina). I think us fans get wrapped up in our own team too much, saying we always choke , when in reality it’s just hard to do, statistically.
A better way of looking at it, to me, is over a larger time frame. This smooths out the small sample size. If we had this same team for 5 years in a row at roughly a 20% chance of making a Final Four, we should expect 1 Final Four. And that’s very nearly what happened - this year was probably the 3rd or 4th best team we’ve had since 2017, and we had about a 95% chance of having 1 Final Four with 0s on the clock in 2019.