I think we need to get into the minds of a woman posting her long hair online, especially ones that aren't just typical instagram models who happen to have long hair, but women specifically posting videos, images, and creating a brand around their long hair. These women are sometimes making a living off of this, or at least are getting some kind of payments/sponsorships.
There's zero doubt that they like the attention. They want the likes on their posts. They want the views. They want comments. But most of them don't want to see "how the sausage is made." I think a lot of them really believe that most of their viewers are women who just appreciate and want to see long hair posts. It's a competition with other women type of thing. And I'm sure a good portion of viewers are this type.
If comments and messages are simply something like "Beautiful hair!" or "Wow, you really take amazing care of your hair!" this is unlikely to get a negative response, even when it's a man saying it. But unless it's specifically a fetish model who is actively catering to the crowd, they don't want their hair to become 100% sexualized. Which is fair enough, especially in a public forum where they're trying to present as a brand.
They want to live in the illusion that while they know men are attracted to their hair and may even be masturbating to it, they don't want that shoved in their face. They want the attention and positives, without fully acknowledging that a huge part of their success is men masturbating to their hair. Or at least they don't want a constant stream of comments and messages like "I want to cum in your hair" or "God your hair turns me on." They "know" but they don't want to KNOW.
I don't think we're doing any favors in helping to keep this content going by being creepy, even though the fact is hair fetishists are a huge reason why they're having any online success. They want to pretend that their success is only because of women admiring their hair, and hey, I say let them believe it because it keeps more content coming our way. Like the posts, maybe comment (if you can be non-sexual), but don't message them, don't post super sexualized stuff, and don't force the truth in their face.