I don't think the animosity towards Mims is justified. Guys have very short windows to make their mark. You don't make it your first couple years, you could be done. Your potential career earnings can plummet. Literally everything is at stake for these young guys.
It's clearly not working for him here. I know reports have questioned his ability to grasp the playbook and things like that but I don't remember anyone questioning his work ethic--and to the contrary, it's usually praised. If he's putting in the work but can't figure it out, whatever, that happens. I can't be angry at a guy for that. As long as they put in the work, IMO that's all you can ask for.
And so he asks for a trade because he hears the team say they're not going to release him, but also recognizes he's absolutely buried on the depth chart. I don't think it's unreasonable. He didn't even torch the team on the way out or anything.
The situation is disappointing but I harbor no ill will toward the player. He just wants a chance to make it, a chance he doesn't seem likely to get here.