Dame played fairly well in the Olympics so I hesitate to believe he's washed. I think it's a combination of the new ball, less rest due to Olympics, and crummy environment with the coaching change and lack of roster upgrade causing frustration. I also suspect he has played fewer games alongside CJ this year than in years past, so there is no other threat to take the focus off him.
I can only think of a few teams for whom Dame has real value this season. Most prominently the Lakers, Clippers, Sixers would probably all be better with him on the roster. I'm not sure what they have to offer would interest the Blazers, though. If Portland wanted Simmons that deal could have been done long ago, so I can't imagine that scenario playing out now. Dame could potentially elevate Chicago to real contender status but not sure they want to mess with their chemistry or have the pieces Portland would want. Denver might swing for the fences to avoid wasting a year of Jokic, sending some package of Bol Bol, MPJ, and picks for Dame, but that would probably be short sighted.