The coaches you mentioned accomplished a lot more in previous seasons than Fran ever has. Look at Dantonio's previous six seasons before his bad year. 39-9 in conference games. I'd say he was getting it done and had earned some good will, to say the least.
https://en.wikipedia.org/wiki/Mark_Dantonio
KF had won 2 conference titles, four Top 10 finishes, won the Orange Bowl a couple years prior to his 4-8 year. Not to mention, KF's buyout would have been HUGE thanks to our AD.
Matt Painter had also had some years finishing 1st-2nd in the conference. Purdue was in a bit of a lull there, but they've bounced back again.
There was prior proof that those coaches would be fine.
Not that Fran hasn't had SOME success at Iowa, but not at the levels the other coaches you mentioned have had. Not really an apples to apples comparison IMO. I'm not saying fire Fran NOW, but this would be a bit more valid of a comparison if he had won a conference title, had a deep NCAA run or two, had teams finish ranked in the Top 10-15, etc. It also would be easier to accept if this team was at least showing some promise despite the L's, but they're getting their doors blown off.
As for Fran recruiting well, it's hard to accept that when his 2014-15 classes were total disasters. That's biting us right now.