I'm asking this as a ligament question, I just want to make sure.

No, it doesn't Go to https://www.speedrun.com/sm3das to submit runs on the 3d All Stars version

But can I still submit it as a speed run in super mario 64.

You can't put it up on the SM64 board, but you can put it up on the All Stars board, which has been linked in Cookie's post

You need to do the allstars leader board

The category extensions does accept switch runs but some of them are not possible on switch https://speedrun.com/sm64memes