While a lot of forces in the industry are not our friends, they're also not our enemies.
Good thing he focuses on the ones that are our 'enemies', then. Like it or not, Jim is becoming more and more of a leftist YouTuber as years go by, which gives him a systemic lens that will necessarily identify companies such as Activision as 'enemies', and many of their decisions as predatory and greedy as a necessary function of corporate capitalism. Of course, when he does that, he doesn't (and shouldn't) target individual developers or employees within those companies, but specifically the higher-ups, the ones who call the shots, the CFOs, the investors, the high-level managers, the shareholders. That's an integral part of being a leftist critic. If anything, him leaning more and more towards the left is a logical consequence of identifying those issues with the games industry.
But to address your post more broadly: if I hadn't watched the video and went solely by what you said, I'd think Jim is ready to stop making positive videos altogether. But he's not. As is very clear from watching the video, yes, the negative/critical videos will keep making up the majority of his content (especially the Jimquisition episodes, I'd gather), but he still intends to make other kinds of videos too. He wants to make more investigative work. He wants to do critical analyses of games he likes, and he'll make them. You heard him say it in the vid: he is extremely proud of his Dark Souls video - as he should be; I found it very interesting, and I haven't even played the games.
Now, if I had one criticism to make, it would be this: I do agree that just saying "people like the negative videos more" is not enough. I don't think it's a bad argument, because making a living in this day and age, especially as a video creator, is a hustle, but it's not sufficient. It's not even the
only argument he makes, but he emphasizes it so much that it drowns out the rest. If you focus on that argument too much, you open yourself up to criticisms like the one you made, which roughly boils down to "oh, so you're in it for the money?" To be clear: I don't find that an especially strong or sufficient counterargument, but it's an easy and understandable one. Like, er... He has a right to make a living off of his stuff, doesn't he? He even has a right to be clever about it and tweak - to an extent - his content to make it more palatable and attractive. That doesn't automatically make him a greedy, opportunistic, disingenuous asshole, as long as he still enjoys it and puts in the work.
Speaking of. If I were to make other arguments for him, I'd start with "I like making videos about those topics" because, well, it's true - I mean, assuming he's being genuine when he says so, which I think he is. Like, he's not
forcing himself to attack corporations. He doesn't make content to be advertiser/sponsor-friendly. That's just his thing, and the industry keeps proving him right. He has no obligation or duty towards anyone to tackle other topics, or to really tackle them in a specific way if he doesn't feel like it. And when he feels like it, he does... With the understanding that it would hurt his livelihood long term if he made it his primary focus. Let the person who's never tried to tweak their work to make it more appealing cast the first stone.
The other argument I'd make if I were him is: "find channels that have the same focus as me and do it better". Do you know many? Cause I sure don't. I mean, I'm sure they exist, but they clearly do not make up the bulk of video game content on YouTube. The reason why Sterling's niche works out so well for him is that he's one of the few people who do that, let alone with some amount of effort. If you want that kind of content outside of him, your best best is to turn to written media and seek out people like Jason Schreier. But that's a very different medium, and very different kind of work still. On YouTube, you'll mostly find alt-right/anti-SJW shitheads and controversy chasers. Ghouls who post 5 videos a day to complain about something that might have offended their stereotypical view of women or something. Outside of that, Video games on YouTube is 90% let's plays, game reviews, top 10s, the history of specific developers, 5% are deep dives on games (see people like Noah Caldwell-Gervais) and specific aspects of game development (e.g. game design, animation, hardware, etc.), and the remaining 5%... Shit, I dunno. The point is: very, very few content creators focus on the industry, much less with a critical lens. Don't complain that Jim Sterling; complain that there is no alternative to him. I, for one, would love it if someone with a similar leftist angle came out and gave Jim a run for his money. He's not a perfect journalist; nobody is. But the problem isn't that Jim has the point of view he has, or that he makes mistakes sometimes (which he always acknowledges and tries to fix, btw), or even that he doesn't go deep enough. It's that pretty much nobody else does what he does.