I think the big problem is that gamers follow the trends, and often, the streamers and reviewers who make them.
I just think of Fallout. Fallout 76 specifically has been a thing for years now, and never got much traction. Now all of a sudden, everyone is playing it along with Fallout 4 (granted F4 had the next gen update and was a well regarded game).
I see Dr Disrespect playing a lot of Halo Infinite lately. I mean... I know it has had some updates, but why didn't this game get more traction when it launched?
I honestly don't think it is a sequel vs a new IP, I think gamers are too trendy, and often passing on good games right in front of them.
For people who remember Titanfall 2's launch all those years ago (crammed in between a COD and BF game). People HATED that game, and it died off before it got going. Over the years a Youtuber picks it up and it gets a revival. Now, people are screaming for TF3. Well, you sh** all over TF2 when it launched. I remember buying TF2 and playing it, only to find the servers dying off and everyone hating the game.
I'm not talking about games that launch in an awful state but get fixed, but games that launched and just never gained traction.