My youngest stopped having parties (didn't want them by HS) at 15.
My older son had a surprise sleepover at 16--but he still was getting together with friends for bdays at 17 and this year at 18. The difference is parents weren't involved ---they would just go chill at bday person's house--the mother might have cake if they knew it was happening--pizza, etc.
I think there are bday people and non-bday people

. I always hated a big fuss for my bday--prefer to let it go...yet I married somebody that loves bdays and surprises and always goes big on my bday (to which I'm embarrassed). Lots of surprise parties over the years and surprise bday dinners, etc.