Do colleges care if you have an art Instagram with 50k followers? Would this have any positive impact at all or would it make them think that you spend too much time on social media?
I think colleges care that you are a talented artist, or that you have been successful in something involving art. I think followers can be used to support your success. I would not be concerned about them thinking you spend too much time on social media.
an art instagram with 50K seems incredible! It shows commitment to a practice.