I'm not sure what I think of today's friendship quote. I've always found a diverse set of friends to be life-enriching, and it helps my diversify my thinking.

It could also be said that the more you are around someone, the more like them you become, so if you start out unequal, you will eventually equalize anyway. I guess for this instance, the quote would mean “don't pick friends that will change you in a bad way”.

Someone that fights for/supports equal rights for all could also argue that you couldn't have a friend not equal to yourself.

I agree. I for one have no friends equal to myself. The differences that
separate us are what unites us. But in a non literal way, we stand on equal
ground on certain aspects.