I feel like 75% of Mastodon are people talking about Linux. If you don’t care about Linux you feel alienated. I enjoy Mastodon and Lemmy, but the lack of more diverse subjects gets to me if I browse for too long.
Update: I took your advice and purchased a laptop for Linux, and now I care about it! Problem solved.
I don’t do gaming and don’t understand or use Linux. But I have found lots of cute cats, dogs, beautiful photography on Mastodon. Also had occasional conversations about books. I would suggest that you consider keywords of what kind of content you want to see and browse hashtags of those keywords and interact with people.