The question is: why do people do this? Some of these channels aren't small so it can't be only some kids on 4chan having a laugh; some are giant content farms that seem to be managed as a coordinated, money-making business.
See also: Elsagate.
Seems more likely than being part of an ongoing effort to destabilise society by disseminating disquietude and distrust, probably.
It's extremely cheap for say, Russia to throw a few bucks at some random bloggers, YouTubers, content creators and fringe groups causing enough distraction and chaos in society that all the good things we create end up being poisoned and society crumbles. (direct or indirect, it doesn't matter - advertising/sponsors/fake news/guest blog posts yaddy yaddy yadda)
Videos like this have two courses of action - they cause turmoil - people see this as bad behavior that should be stopped and is immoral and corrupt but then they have a trigger response.
The response to this content, conspiracy, turmoil justifies their means. When government/regulators/youtube step in and ban it then that is "big ol guvment and conspiracy and big brother violating their rights"
Which begs the question of why in ANY democracy its citizens would be fighting to poison its democracy unless there is an external force funding, supporting and training these actors. Or is there just a growing psychosis we're ignoring of people with mental problems we're ignoring?
Your Russia comment may have just been a throwaway idea, but it is also a good example of one of these stories. The literal losers of an election invent a conspiracy to rally themselves around because it is really hard to accept that they lost.
To your second point. Lol. Your language suggests that losers are only mad because they lost and you frame it in an overly simplistic way - ignoring the fact that Trump's campaign is under investigation and has what, 34 indictments? If that is a conspiracy theory then conspiracy theory has no meaning and well... good luck.
I don't agree that it is mainly the olds who fall for conspiracy theory. In fact, I think that sort of thinking among young people is a sort of conspiratorial idea... The dumb boomers didn't vaccinate so its up to us young people to brave the odds vaccinate ourselves (even though only 1.3 percent of children are unvaccinated, it is unclear for what reason in every instance, and 50 year olds typically aren't in charge of vaccinating kids because... 50 year olds usually don't have children for obvious reasons. It is gen x and millenials not vaccinating their kids...). Again, conspiracy isn't exactly the right word. "Conspiracy theory" is just a tool to accomplish the same thing. I don't know exactly what it is... Give oneself some sort of importance?