As a response to a motion to dismiss or summary judgment, this is fine. They are pretty similar, and there's a lot of overlap in the creative process with an aborted ER reboot or sequel.

It's fair to ask a finder of fact decide if they're similar enough for it to matter, and, critically, how much the Crichton estate lost due to that. Now they just move on to the part where they can say, "Most shows in an ER are going to have this, that, and the other similarity, and Character X was inspired more by 'Non-ER character Y' than by anyone else."

John Fogerty of Creedence Clearwater Revival had a very shitty record deal, and ended up having to literally play his solo stuff in court and describe to the jury why the one CCR swamp-rock riff was different to a later one he wrote for his solo album. He won, but they are pretty darn similar: Run Through the Jungle vs The Old Man Down the Road. The case actually went to the Supreme Court over legal fees calculation, but that's not the relevant point here. Just because we look at something and think it's not very likely to win doesn't mean there's no relevant dispute over facts to resolve.