I think in today's climate of college basketball, and they way outside money has become a big player in decisions inside an athletic department, you are going to need a bunch of people on board to really feel comfortable. AS a HC, you don't just need the backing of your AD, but you need the backing of all those who pull the NIL strings. One thing I am certain of, as a regular participant on this board, is that not everyone who follows Illini basketball is totally enthralled with BU.
If some of the big fi$h feel the same about BU as some of the commenters over the last few weeks, I could see where a guy might suddenly feel less comfortable in his "dream job". Sometimes it's not all about money. Sometimes it's about support, security, and wanting to control your own narrative. (leaving as opposed to being asked to leave)
Disclaimer: I have zero actual knowledge about what the heck is going on...