I have a strong feeling that the proliferation of highly marketable Mascot Horror is due in part to the dirth of modern kid-friendly media that dares to try and be spooky. As family friendly shows and movies become more and more sanitized, mascot horror feels like it's filling that gap. Indie creatives have capitalized on a market that has always been there but has been effectively unserved for like 5-8 years? No wonder it's exploded in popularity.
Of course there are exceptions and this isn't an all-encompassing rule, and of course there are other factors to mascot horror besides crude capitalist market analysis, but I feel like the sanitization of media at roughly the same time as the rise of this sort of "edgy but kid-friendly" internet media are too correlated for it to be entirely coincidence.
When I was 4 (?) my mom was hesitant to let me watch Anastasia (the Don Bluth movie from 1997) because she thought Rasputin was gross and would give me nightmares. Fortunately for her, I thought his villain song fucked:
