I'm a Maryland Terrapins volleyball booster, so I thought I'd weigh in.
I think IU actually cared about volleyball, at least in terms of wins and support from fans. The Big 10 dominates women's volleyball (along with the PAC-12) and the schools take it seriously. Some have per-game attendance in the thousands. Most B1G schools don't want to be left behind, ashamed of their performance next to Nebraska and Penn State (which IU was, arguably). If nothing else, Aird's huge salary is an indicator that IU wanted more. Aird has a rep as a promoter too, wanting to build popularity and support for his team. I think he saw the new arena as a commitment on that front from IU. That said, according to my sources, the big paycheck is what drew him to IU.
His 15 players who left IU seems to include students who simply graduated but had a year of eligibility left, which is to be expected. But he had two star freshmen leave after a year. I count 3 more good players who left the sport or popped up at another school after taking a year off. That seems high. The worst blow is the loss of his star recruit in February, which is very late in the process.
I was bitter when he left Maryland, I confess. The school's entry into the Big Ten and Aird's hiring infused real energy into the program. (He was assistant for a legendary PSU team). So recruiting took off, with 4 or 5 top players committing or signing. But when he left, most of his top players/recruits left too. He was about 2 years short of "turning Maryland's program around". Now we're kind of stuck in the bottom half of the conference.
Yes, some UMD players really loved him. One said she was heartbroken when he left (she's now a pro). But another top player suffered a concussion and quit mid-season even after she was cleared to play again. She transferred out before he left and later wrote scathing words about the program, calling it a "toxic" environment in a senior reflections piece about her college career (which she subsequently edited). Maybe Big Ten coaches feel licensed to be tough. I found this https://www.heraldtimesonline.com/story/sports/college/2018/03/09/aird-says-hoosiers-need-a-little-sauce/46874903/
Anyway, good luck. There are lots of good coaches that won't cost IU nearly as much.