I'm no expert, but this sounds like a learned response reinforced by the fact that most popular things genuinely aren't high quality, that it's easy to transfer the negative feelings associated with ads onto their subjects, that most people's opinions (at least as usually expressed) are pretty shallow and often not more substantive than ads themselves, and maybe a dozen other smaller things.
The only thing I can think to suggest is exposure therapy, finding and experiencing popular things that you actually end up liking and/or opinions about popular things that are more substantive. For me, this would look like:
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Forcing myself to watch popular things I've already identified as things I'll probably like, and just powering through any aversion.
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Picking a piece of media I like, finding reviewers who seem genuine and have good things to say about that thing, looking at other things they've recommended that might be more popular, then watching those things.
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Watching video essays about popular things that more thoroughly defend what's intelligent, creative, underappreciated, etc. about them.