@Sutinnit
As someone deeply in love with weirdcore, I agree with you completely. I have a lot of feelings about that subreddit for this exact reason, especially with how they say illustrations falling into the Weirdcore aesthetic would be better hosted on r/Dreamcore. It's so disrespectful, and although I do think the word Aesthetic and the word Lifestyle have considerable overlap (so it's fine to make a scenecore page on an aesthetics wiki, for example*), I definitely feel like this era of giving things labels for tagging videos instead of for describing and expressing yourself has made a lot of communities worse.
To the main poster, though... I don't think it's good to take issue with people giving themselves the label of an aesthetic. Finding communities of people who share your interests, aesthetics, lifestyle, etc is HARD. Making a word to encapsulate the "vibe" of it helps a lot in that process. And more than that, it helps to describe yourself. Being able to describe yourself with words is really important. It's why people talk to themselves when they're alone. Language isn't just to communicate with others, it's there so you can communicate with yourself.
*I haven't seen the scenecore page, I don't doubt that it's bad LOL this is still a new wiki that needs help. Maybe you should edit the scenecore wiki?