There are three things that current Game Theory fans that come on every single critic video to defend their favourite channel are either unaware of or are overlooking.
The first point is that the original fan base is mostly gone. We stopped being the targeted audience at some point during the channel's history and you cannot disregard that fact. The changes are drastic from the last video I watched to the new ones. Try watching older videos and you'll see what I'm talking about. You can clearly see it in the channel's evolution. So saying that Game Theory is only trying to appeal to its fans is a half truth: Game Theory abandoned its older fans and instead went for a new audience and are now strengthening the loyalty of this new audience. The way I see it is a bit like how Nintendo went from a Hanufuda company to a video game company. The old people playing cards are a different kind of customer, they're not the same as early gamers. Nintendo is simply not interested in that market anymore and that's what is happening with MatPat's videos. This is also our own fault at understanding the situation: it's not that the content became worse (or better in the perspective of the new fans), but that the channel reinvented itself.
The second point seems minor in importance but has ultimately larger implications. You see, the meaning of the word theory is often confused with the meaning of the word hypothesis. A theory, especially when used in the scientific context of early Game Theory videos, is an explanation established on solid observations which were conducted through a rigorous scientific method and as such are on the level of proven fact. A theory is not a mere explanation, it can contain facts and laws. If we were to put the two terms on a pyramid scale, the term theory would be at the top, while the term hypothesis would be just above "nothing at all" and below the term working hypothesis. That is why there are worldwide shock waves when a theory is proven false, because it literally implies that all we knew about that specific matter was a lie and we have to go back to square one. But when you have a hypothesis, you're already at square one! You're simply trying to make sense of something you don't quite understand.
Of course, we know that MatPat's videos will never feature an extremely rigorous approach to the hypotheses they show in their videos, but as a channel that once pretended to and which still uses the word theory in that specific context despite how they end each of their videos, I would expect that their videos are based more on facts than half assed research and that they correct their mistakes when pointed out so as not to mislead their viewers.
The final fact to consider is that MatPat is absolutely, as well as purposefully, blind and deaf to criticism. I admit that I admire mat for ignoring his hatedom's most trollish attempts at communication and I hope that he continues in that direction. However, I cannot help but sigh when I see how he deals with constructive criticism and how unwilling he is to admit that sometimes, just sometimes, he happens to be wrong! You can't always be right, you're bound to make a few mistakes along the way. But MatPat outright ignores any contradictory opinion to his and this is so painful to look at, because it makes him look very bad as a human being. Especially when the contradictory claims are backed by evidence. Game Theory will be able to claim that they listen to their fans when they will show sportsmanship and listen to what all their fans have to say, not only the ones who share their biases and opinions, because then that's continuing the legacy of splitting their community in two.
A closing word: You say that Game Theory has more fans since they began their new format? Then I'm ready to wager that their channel would experience an even more massive growth if they addressed the second and third points!
...the odds of such an event happening are within the realm of possibilities of this universe. ~ What my brother says when questioned about the validity of a claim