I don't see an actual issue here. Everyone is exercising their 1A right to free speech.
Kimmel (and of course, Comey) can say whatever very non-funny thing they want about having others kill Trump for them, aka they didn't directly threaten the POTUS. They're evil, but not stupid, so they covered themselves.
Trump can say whatever he wants about a tool the demontards used against him. Personally I try not to speak ill of the departed, but that's me... it's not a law.
People of all political views also have the right to react and say whatever they want about what has been said. People can address their grievance directly with ABC, and let ABC decide what to do with the sunken hole (ratings-wise and cash-wise) that is Kimmel.
People who hate Trump probably can't ratchet it up too much more... but they always seem to, somehow. So they can have at it. Sure, why not send one more email to your congress-person telling them to impeach Trump. Go enjoy yourselves today.
Everything is working as intended by the Founders, as near as I can tell.
