It's sort of a weird argument in general. Strictly speaking, a lot of companies don't need advertising, in that they're not going to go out of business without it. Advertising isn't usually about literal need, it's about doing something that benefit the company. Advertising does this both in tangible ways like larger profits, higher sales numbers, larger reach and in more abstract or difficult to measure ways by increasing brand loyalty, awareness, community building, fighting competition, etc.
Advertising continues to benefit Nintendo, whether they literally have a need for it or not, which is the point people are making when they are critical of Nintendo's perspective on creator content.
I mean, you're not wrong on those things, but I don't think those two circumstances are mutually exclusive. Yes, watching videos on particular things of interest to you might cause you to find and follow particular creators, but it's also true that watching videos on particular games does also cause those aforementioned benefits.
It works both ways, and I don't think one being true is an argument against the other being true. I think both of those cases are very much true very often.
I know you're not. Part of what I am trying to say is that I don't think this is a case of the benefits being so marginal that they are apathetic to the issue, I am saying that I really believe this is an issue where they are genuinely ignorant of the benefits entirely, and are making poor decisions based on that. Some of their past decisions and their ongoing evolution of their approach to creator content seems to indicate they are really just really, really, living under a rock with this stuff.I'm not trying to claim it's not helpful at all, I'm saying that it's not helpful enough for them to care it seems.
Like I said, there is a reason why every other major pub/dev supports YouTube content including others that are arguably in a similar position as Nintendo. Call of Duty doesn't need brand awareness. World of Warcraft doesn't need to reach new audiences. Bioware isn't going under without creator content. But all of these franchises and games and companies have seen a huge value in allowing that content and their respective communities to flourish because ultimately it benefits them as well in a lot of ways. Nintendo not being on that boat isn't because Nintendo is special, it is because Nintendo is being stupid.