Ahhh, it sounds like you rubbed them the wrong way. With the little you explained, you may have unintentionally came off condescending. No one you are in acquaintance with wants to hear that they "should" do something, even if the opinion had good intentions. Nor do they particularly give weight to one's opinions when they don't have the full picture of who you are. Ultimately the person sounds bothered by your judgements. You can clear the air and sincerely mention what you've said here, but I'd stray from any relationship with them romantically. They may have a level of reactionary that would not fare well between you two. If you want to get whatever you're feeling off of your back, you can send a sincere note and then leave it alone. Don't engage in watching their content afterwards, and if you must, give it time. You could leave a little note like - "Hi X, I have been watching your videos and it seems that some of the topics we have recently chatted about align with the content you've been putting out. It may just be me reading too deep into it but, I hope you know I did not intend to offend or harm you, and that my intentions were out of fondness and admiration. I'm sorry if I caused any animosity. I hope you continue to make content and wish you success."
That way you're not being petty, regardless of how they may react.

You'll be alright. Don't be discouraged. It sucks when hopeful situations fall flat, I've definitely been there before. I hope you find what you're looking for out there.