Why give up a massive salary at TTech where he's successful and loved and calls it home, to be potentially the next failure in a 20 year list of failures at IU since Bobby Knight?
"I realize it's hard to turn down a former 'blue blood' "
FIFY 
LoL, Rivalry, love it!
In all seriousness though, could we all set aside and IU homerism/haterism for a minute and try to look at that program objectively?
What are they today? Can they get back to Knight's glory days when IU was in the small handful of BB Royalty? What should the standard be for an IU coach?
In Knight's 30 years in Bloomington the Hoosiers won three NC's, 11 league titles, and had 24 NCAA tournament appearances (Note that this is more impressive than it sounds because half of Knight's tenure was before the tournament expanded to 64).
Since then:
Mike Davis, 7 years, 2000-2006:
1 league title
4 NCAA appearances
Kelvin Sampson, 2 years, 2006-2008:
0 league titles
1 NCAA appearance
Dan Dakich (interim)
Tom Crean, 9 years, 2008-2017:
2 league titles
4 NCAA appearances
Archie Miller, 4 years, 2017-2021:
0 league titles
0 NCAA appearances
The Purdue fans do have a point. In the 21 years since Knight's firing the Hoosiers have three league titles (one every seven years) and nine NCAA appearances (roughly every other year). Both of those are WAY off from Knight's pace of roughly four NCAA appearances every five years (including before expansion) and a league title roughly every three years.
Was Knight simply lightning in a bottle or can Indiana get back to (or at least close to) those heights?