Recently I made a speedrun attempt of Barnstorming which was released in 1982, as I submitted the run I'm wondering to myself "what is the oldest game on the site?"

https://www.speedrun.com/Stunt_cycle
Stunt Cycle was released in 1976 for the Atari 2600

(However there are other games with earlier release dates listed, but it's bogus data. For example, see: https://www.speedrun.com/coffeekid

dragster was 1980 so its younger than stunt cycle. There are 8 game that are older than dragster as of now.
There is also a filter on the all games page that let you select the year you wanna check.
Or you can jsut change the date of this link https://www.speedrun.com/games#year=1980&sorting=playerCount&direction_sort=on

the oldest game as of now is computer space from 1971

Oldest game on the site?

Cuttyflame