I think most people recognize that the high strikeouts do make Mitchell a significant risk to flame out. Certainly they also present a big upside for him in that if he does stay healthy enough to really get some serious ABs he might really find some adjustments that help him cut that number down. On the risk side, seemingly anything that gets him out of whack could really lead to looking completely lost really fast. Possibly the bigger one though is that he is approaching that mythical peak age. So if he doesn't make those adjustments, father time stealing that small fraction of youth could also start to push the K rate higher and everything falls apart that way.
In the meantime though he is producing and giving some of the other potential replacements the chance to get some more seasoning (Lara, etc) and that is pretty helpful.