I'm old now, man. I'm on the back 9 of my drinking days.
Same here lol.
While my tolerance is in peak form so I almost never get hangovers, which is awesome ("that's actually not really awesome"---my physician and my liver, probably), I get sleepy way more quickly. The days of late-night drinking/partying are many, many moons ago...and I have no complaints.
Middle-aged with a toddler, so it's bed time by 7:30-8 for me (except when it's Jets Christmas as it is now).