You can't compliment someone's intellect without actually knowing them. As I understand from the society made rules, usually the compliment has the role of sending friendly signals to the new person from the group, along side with the typical hello

Also, I kinda have a different (maybe dumb) perspective about this... But in general, for me, compliments can be:

• an opinion - when it comes after you show something you worked on... even looks... there were some minutes/hours sacrificed for that look, so it can be legit... because no matter how beautiful a person is, if they don't put some effort in personal hygiene,

• hypocrisy - when obviously the other person has something to gain (including the respect of the group of monkeys from which the presumed shitty person who doesn't deserve the compliment is a part of).