I searched for a fish related video on PeerTube and put the URL (https://video.ploud.jp/w/ddbf542e-d4b6-4778-abed-8c51799188a4) in the search bar of my Lemmy instance, after a bit the video was available like here just as a regular Lemmy post. You should now be able to reply to it from Lemmy.
If you would just stick to playing games on the Quest 2/3 directly that should be fine. The Quest 2 can run basic games, so it does limit you a bit. For example VR Chat has some worlds with too many assets that are not playable on the Quest 2 directly. From what I remember you would be limited to Meta’s store though.
Unfortunately VR seems to be a niche thing so I doubt this will get a lot of priority on Linux.