I don’t think there is anything he can do at this point to regain his previous popularity. Even if he were to reappear as Cosmo tomorrow people aren’t going to just forget the tranny years. He’d probably do okay, but the glory days are gone.. and not just for him.
I have to imagine speedrunning as a whole is in decline. The most popular games were always old titles, and now we’re past the ten year mark of them being broken down. That new OoT thing is good example of what this leads to - less actual game being played. Outside of the speedrun autismos that novelty of “guy just beat oot in x minutes” is over with.
I agree with the first part, but not so much the second. In fact, I think the second part is actually one of the reasons I don't think Narci can ever go back to the Cosmo days. When Cosmo was a thing, speedrunning was significantly more niche. There were still communities, but I'd say in the last few years it has seen a pretty significant surge in popularity. The "done quick" style of events are certainly the big ones, but a bunch of other community events have spawned from those, plus Twitch is a much bigger thing now so the number of notable runners has grown. I don't know if any are really on Cosmo's level, but that's because there are so many personalities now that it's more spread out. Even if Cosmo never trooned out, I think his audience would have become more diluted just from the number of speedrunners growing.
The final time is certainly a big part of speedrunning since, well, that's the point, but I'd argue the techniques that go into getting that time are the bigger deal. There's a reason people who get the skipped named after them tend to be the more recognized person, even if they don't actually hold the #1 spot on the leaderboard. I think that was also part of what made Cosmo noteworthy in the first place, to the point where people still knew his speed running exploits even after him trooning out/other people beating the record.
If all Narci is doing is getting WR on someone else's techniques...eh, he'll probably get some attention, but nothing near the Cosmo days. The views he does get will probably be more nostalgia based than anything else, and I don't know if he'll be able to hold them once people find out what happened to him. I think he'd have to do something bigger in the community to even have the chance of becoming notable again, and even then, I still think he'd struggle to reach the same levels as his earlier Cosmo days just because of the sheer number of well known runners in the mix.