It’s actually quite a versatile term. Being in a bubble simply means living in your own world. This can mean many things, such as rejecting views that dont line up with your own. Which is exactly what you are doing. I laid down a straight fact that art is subjective, and you said no. You are wrong, but you would rather live in your bubble where you are right than accept that you are wrong.
You are even wrong about what being in a bubble means. In that, you think its meaning is strictly one thing. When in fact, it’s really quite subjective…
Edit. Oh god, did you just say you are smarter than most people? Thats so bad. What are you? Like 12 years old?