I’m in my early 30s but look a bit younger, and usually fly in jeans and hoodie (I work for a record label so this is business attire for me). Routinely at LAX in the Priority line, I get “Sir this line is for business class and elites” to which I usually reply “I sure hope so” and stand there awkwardly until they pull up my PNR and realize I’m exactly where I’m supposed to be. Haven’t really run into this issue at other stations, just LAX.