Okay so as someone who's been through this awkward phase of trying to get someone's attention and has finally gotten past it, here's my thoughts on it

Yes, to an extent its seemingly a bit manipulating. You're basically making one error which changes this from cute to manipulation.

You're on the right track, trying to find out what they like and so on is incredible cute and exactly what people want because they want to know you care about what they like. Your error is that it doesn't sound like you're actually trying to enjoy the things they like, you're just pretending you do to get there attention which will backfire when they do take the bait, become closer to you and simple ask you some random question on the topic and you completely fail to be able to respond in anyway. That will severely ruin the relationship or friendship.

What you need to do is listen to the music they like, see how you feel about it and discuss it with them then. Make an actual common ground for you too to both enjoy talking about and trust me things will flourish.

Alot of people in the comments saying this type of behaviour is harmless but it's honestly not because that person will feel used and lied to when they eventually find out you just said whatever they wanted to hear to gain their trust. It's not worth it.

So ya, keep doing what you're doing but add that crucial step of actually indulging in the content you said you are, get a bit of common ground between ye do to that and you'll be doing amazingly