It's deserved. I've never been a Souls fan in any way, but I do not exaggerate when I say Elden Ring might have perfected open world. I usually dislike open world because it's never truly open, but this was. They let you just go wild. And most of the things I disliked about Souls were made better with the open space. And the things i did like about Souls I could finally appreciate as a casual non fromsoft fan.
As a man who never cared about or liked Souls games, I think that says a lot.
It depends on how aggressively they push it in sales and if they offer any substantial DLC, IMO. I can't help but think that Witcher 3 and Skyrim reached their lofty heights because they saw things like price decreases physically over time that felt right, and things like annual Steam and GoG sales that seemed to get lower each time.
If Bandai pulls a Nintendo and never reduces the price or offers it in sales, then sure, it will probably top out around 25m - 30m.