'Crashout szn' (= 'crashout season') is current Gen Z slang for an ongoing period of someone (or everyone collectively) making chaotic, irrational, self-destructive choices — texting an ex at 3am, quitting a job impulsively, going off the rails. The 'szn' is shorthand for 'season'. If your teen jokes that it's 'crashout szn', they are commenting on a stretch of bad decisions, often half-seriously. Worth gently checking in if it sounds more serious than playful.