I would say its still very popular, though it is over saturated now. As you say there is a lot of channels doing things relating to gaming though everything does seem to have been done before - even if you take a newly released game within a week, or even a few days in some cases you will see tons of pages of results if you type in the typical "gameplay", "walkthrough" or "lets play" searches of that game.
There are many games that have had their content sucked out of them (Minecraft, Mario, Mario Kart)
I still think the gaming community across all of YouTube is still well alive. You can see the same game played but in a different way, and with different styles of commentary and comedy. I wish more people would be open-minded though and consider this, rather than saying "oh you're copying this guy" because a YouTuber with 1 million subscribers played the game already.
Gaming community will never be dead.
The thing is with now-day let's play channels is they do only one specific game rather than many games, look at these Minecraft, call of duty, battlefield YouTubers, they over saturate their youtube channels which people have grown tired of, if they evolved older games and along the other things, I bet you that their channel in some aspect will grow ever further up as it goes.
I've been part of the gaming culture since the beginning of YouTube, even though I had no computer power to make them, I did enjoy them relatively well - of course there are channel that does multiple games at the time and upload them a day separate from the other upload (like I am currently) but those channels are hard to be found now and it's dissatisfying.
So, that is just my opinion and input, I understand where you are coming from, but for now, I said no in the vote.
The thing is with now-day let's play channels is they do only one specific game rather than many games, look at these Minecraft, call of duty, battlefield YouTubers, they over saturate their youtube channels which people have grown tired of, if they evolved older games and along the other things, I bet you that their channel in some aspect will grow ever further up as it goes.
I've been part of the gaming culture since the beginning of YouTube, even though I had no computer power to make them, I did enjoy them relatively well - of course there are channel that does multiple games at the time and upload them a day separate from the other upload (like I am currently) but those channels are hard to be found now and it's dissatisfying.
So, that is just my opinion and input, I understand where you are coming from, but for now, I said no in the vote.
I don't think the gaming community is dead but I do think it's very over saturated with a lot of just "garbage" and it's really unfortunate for small channels that really want to grow and be apart of the wider youtube gaming community.
I think the gaming community in a sense isn't dead but I do agree that you do see a lot of the same content. HOWEVER, when I watch YouTube videos on games, I watch it more for the people playing it - meaning I react to their personalities as opposed to the gameplay itself. Although everything has pretty much been done, yeah you might get some views because you do a video on a new game, but it's your repeat watchers that watch your videos because of you, not that game. Your videos really are what you make of them, just be yourself, and make sure to use a mic and focus on editing, that's what'll set you apart in my opinion! 
No sir lol the gaming community is booming..if not more than ever at this point. I believe that with Youtube it has expanded the reach of gaming
