You've built your argument around some false takes: "vast majority of Tenz fans is people who watch competitive Valorant," and "people will change their idol real quick."
Yes, his initial boost in popularity came from that, but the main wave and growth came from his streams, YouTube, viral one-tap clips, and insanely viral clips with Kyedae. Tenz has long been more than just the "Glorious NA GOAT who brought home champs", his personality and personal life have played just as big a role for a while now. It's a different level of media presence compared to all other pro players and unique coincidence of factors (like having a wife who is in the top 5 streamers for Valorant).
As for the idea that champions only get a few thousand views - I never said that wouldn't happen. It will, but it’ll only be a few thousand at most, not consistent tens of thousands like Tenz. That’s a different level. (Aspas is more of an exception here because the competition among famous pro Valorant players in that language market is much lower).
I'm talking about his growth as a media personality ONLY if he keeps playing and stays involved in Valorant. If he quits the game, of course, he won’t remain the face of it. But similarly, you can't say for sure that he will quit. There are more factors pointing to the opposite – staying with Sentinels as a content creator, mentioning that he'll do watch parties – this all indicates that he's going to continue building his presence.
Being in the top 5 Valorant media personalities for 2-3 years is a long period, especially considering how short most players' careers are and how hard it is to stay on top. Again, if Tenz wants to continue growing in Valorant as a content machine, he’ll be a media giant for more than just 2-3 years. Right now, he's easily top 2 after Tarik, and there's no one even close to challenging that spot.