I suspect that there is more to this than we have been led to believe.
The gentlemen involved have put their spin on it. The fact that they were in the exit row was not mentioned before.
Having been on many flights with passengers who are loud with the "notice me" vibe. Very plentiful on LAX flights.
One passenger (in F) loudly talking on his cell phone during boarding, snapping his fingers for more drinks and snacks to FA, who kept bring him more and more. Pretty shocked at this but, not my job. By push back, he had 4 drinks and 4 bags of chips and still trying to close his "recording deal".
If the FA was able to assess that their might be a issue with safety (non-compliance or alcohol) then the decision might be to not have that passenger in exit row. Who knows for sure?
I have been in 1C and overheard many conversations regarding FA concerns about passengers who boarded and do not want to comply to their requests. (No, you cannot have lap child in exit row etc)
My 2 cents.