I mean I can accept people not liking the execution if they played through the whole game and could argue their topics straight. I fully admit that some parts may drag, some scenes could be longer etc. However we can say that about 99.5% of games, unless it's a 6hour CoD campaign.
Based on the video you linked, I would say again that a lot of these "reviewers" have hard time accepting that in a character-driven story, characters, at a minimum need to go through a transformation and have an arc. Joel's arc, unlike Ellie's, was very much done in the first game. He was not such a complicated muilti-layered character to begin with (usually people like simple characters or comic reliefs more btw, cause they are simple and funny even though they have very limited depth), he had one major arc: emotional trauma from losing his daughter. By the end of TLOU he reconnected with other important people in his life, found surrogate daughter to love and accepted his sins. His development is complete. I do not see how in that video you linked the reviewer points to him being an "important character" after that point.
Keeping him and giving him a second arc after the whole emotional bonding issue that he had for half of his life has been resolved would be bad writing. 99% of time it leads to bad fanfiction cause there's nothing for character really to do apart from being a mentor, so they are just there to please the fans. Or you'd have to break him again as late Luke Skywalker and see how people hated that.
I know most people like to see more of the same shlock: Luke Skywalker going on crazy adventures, more Darth Vader killing people (Rogue One!), more Jack Sparrow, more Iron Man. But the truth of basic good storytelling is that every major character should have some form of an arc to go through and at some point you just run out of those based on the depth of character: Luke and Darth Vader don't need more context cause their arc was complete in 3 movies, Jack Sparrow (loveable one-note comic relief!) was done in the first Pirates of Caribbean, look how much worse other Pirates movies fared because they simply milked the characters whose story was done in round 1!
I don't expect people to immediately accept Joel's demise, in fact, that's the point of that scene to elicit hatred. But if after 30 hours, different perspectives, world and character building, you're still pissed at that one thing and can't see the other perspective and then call it "bad writing" cause people loved Joel (?) then yeah, you pretty much completed the game but got a fail ending for empathy and relativity. In fact the game pretty much calls out all these people.