Sean Lewis was thrown under the bus earlier in the year because Deion couldn't recruit OLs to protect his QBs, and he was blaming his son getting sacked on Lewis. I'm not sure any good coach would want to coach for Deion now given how other coaches were treated. Tim Brewster just recently left as well...he was the TEs coach for Colorado.
There is a new article in the Athletic that is sort of a post-season review of Colorado with quotes from 1/2 dozen anonymous PAC 12 assistants.
It is mentioned by assistants that they think Colorado will have a difficult time hiring assistants because of how Lewis was treated. They also mention that the TE coach who left is the best recruiter on that staff and that the OL coach came with Lewis and would likely leave if Lewis left.
They also mention that it appeared to have a star player issue with Deion's sons and Hunter being treated differently than others on the team. Specifically mentioned one time that Shedeur came off the field and the OC tried to to talk him and Shadeur simply brushed him off and went to the other end of the bench. They mentioned that Colorado's secondary played soft (including Hunter who was actually targeted alot - 53 times, allowing 40 completions and 5 TD's to go with his 3 INT's) and that Shilo plays hard and is good in run defense, but isn't a great cover safety.
The biggest issue they talked about was the lines though. Basically said both lines were not P5 quality. They also mentioned that lines are not really something you can build through the portal - there simply are not enough P5 quality linemen to do that and that lines are developmental positions that you need years to build. You can plug a spot in a line, but you really can't build a line with portal players. They are also shocked that he only has 1 OL recruited for next season - a 3* junior college transfer.
They also don't believe Deion will be able to play the portal as hard this year due to bringing in so many this past year and how the NCAA is getting more restrictive with 2nd time transfers.
Finally, they talked about how Deion is being very positive about next year (as most coaches would be) but the assistants see some hard times ahead. They said it is the blue collar coaches who do well. The ones that are willing to put in the work and effort to recruit and develop players and build a program and a culture. They think that Deion is starting to see that, but you can't shortcut that - you have to be willing to go through the building process.