People are the issue with nearly everything, people - it's a lazy point to make:
Theme parks? Ruined by too many people
Driving? Ruined by idiot people
Restaurants? Ruined by loud people
Public transport? Ruined by strange and wonderful people
Facebook? Ruined by people who can't spend one minute without sharing a piece of their life/opinion you don't care about
Airsoft is never going to be an exception to that: People shouting 'move up' when not bothering themselves, people offering unsolicited (and often wrong) advice on guns, people who make no effort to include others who've just started, people who leave half way through because they've brought their sniper rifle along but can't shoot, people who don't call their hits - particularly people who run at you and take a few shots before hitting you and then claim it's a straight kill trade, people who over-spam their HPA solenoid engine and give us all a bad name and/or don't understand how Joule creep works and end up shooting hot. The list goes on.
My absolute biggest gripe that's tangible though is hi-cap goddamn magazines (sorry Trigger). Of course I'm not going to say anything (and I own a couple myself out of necessity so probably should anyway) but the noise, the winding, the lack of fun reloading all for the sake of a few more shots. I wish they didn't exist I really do because everything is genuinely more fun when you're not strapped to 2-3 maracas and have to panic reload occasionally.