Not cool
A few pet peeves (yeah these are all first-world problems, don't take it too seriously):
People who don't speak Spanish but insist on the Castilian "distinción" by randomly and incorrectly pronouncing select z's and c's as /θ/, similar to the English th in thing - so for example, when a British DJ pronounces Ibiza as "Aye-bee-tha"
Most other affectations of accent - trying to speak a language authentically and fluently is great, but there is a fine line with cultural appropriation. If you're not from New York, don't try to sound like you're from Brooklyn. And yeah, I'm a chameleon myself so sorry.
Visiting spontaneously without letting me know in advance (yes texting while you are on the exit is fine, provided I answer - I don't need much notice). I have some real issues, so I do not like it when the doorbell rings or someone knocks unexpectedly. So unless you are law enforcement, don't come to my door unannounced.
The postal service or UPS delivering my neighbor's mail/packages to my house. Yes, this happens all the time. They seem to have a particular affinity for this one neighbor whose house number is mine+200 (i.e., two blocks down - it's not that hard).
Yeah no I won't go into anything related to traffic, because I've probably done it myself. Like not starting to drive when the light turns green because you were checking your messages. Or dive bombing in for an exit in traffic (ok I try not to do that, it's not cool). Or going only the speed limit in the fast lane and the music is really good and you're just not paying that much attention and you're on cruise control and you just can't be bothered to change lanes but that guy behind you really really wants to pass and doesn't want to go into the empty lane next to you.
OK one exception: people who tailgate you because they want to pass, and then you let them pass, and then they slow down and hold you up so you end up tailgating them.
OK one more exception: people with out-of-state plates during commute traffic. Yeah, just because you have a ski cabin in Nevada or you used to live in Texas five years ago does not mean your car can have their cheap plates. Look it up. Exception to the exception: if you really can't afford it, I'm good, sorry to bring it up.
People who go to a show because they know one song by the band, and don't pay attention to any of the show (bonus points: talking loudly with their friends the whole time, pushing through the crowd to get more drinks and then trying to get back in front of you) but all of a sudden are the biggest fan when the band starts playing the one song our superfan knows
And a few less funny but obvious ones that are probably shared pretty universally:
People who boo their own team or coach (and people who are a little bit too fanatical about youth sports, or think they are being helpful from the stands).
People who leave before the applause is over at the symphony or show (yeah I know, the garage exit congestion is a pain, deal with it)
Meetings with people who clearly don't want to be there so they are on their phone or laptop doing something else the whole time. Really, all meetings with unnecessary attendees who agree that they are unnecessary.
Corollary: The person who skipped a meeting and then makes you redo all the work or interferes with everything you agreed upon because they didn't know what went on in the meeting (even though they were invited and decided they were not necessary, so "go ahead without me").
Yeah this one is too obvious: Telemarketers and autodialers. And what's with all the calls in Chinese - is that psychological warfare or just lazy market segmentation?