It does feel like Ken is at the end of his arc though. Even Jeremy Strong said the birthday episode was a consummation for the character and he's done all there is to do with him.This. He was blowing bubbles. He was aware enough to respond to Iverson. He didn’t go from that to unconscious unaware drowning in seconds. Show is supposed to go two more seasons, it wouldn’t dare do that without his best actor. He won a Emmy last season.
He took his shot with the Sandi/Stewy partnership in S1 and that flopped after the waiter incident. He took his shot with the Greg documents and getting the FBI & DOJ involved and that didn't play out the way he hoped. He finally conceded and asked to be bought out, and Logan shyt on him and basically told him he's a hostage for life.
I really don't know if they pulled the trigger but I wouldn't be shocked, that does feel like the ending Ken will ultimately have. If he isn't dead then he really only has one play left
definitively give up on ever running the company, sell his shares to Matsson so he can absorb WayStar, and come clean about the waiters death and Logan covering it up