This is one of my largest pet peeves. Professionally and socially.
I feel like the differences are taught in 3rd grade along with the differences of there, their, and they're.
Just got an email from a client who used you're instead of your and got triggered. I find myself judging the root of people's intelligence when I see these used incorrectly.
I've absentmindedly made this mistake plenty of times in my life but I just automatically assume the person who uses the incorrect one is not smart. An aggressive assumption I know, but it's just such a simple concept to grasp, like c'mon.