What scam exactly? What is wrong with want? Most of us want more, but will balance it in reality with affordability. Most buyers of the 4090 know exactly what they are getting. Maybe there are a handful that are rich enough to throw that money without thinking, but if you're in that position it doesn't matter any more.
1, Rich gamer who wants best. Not a need, but if you got the money, why not? I got a 4k OLED monitor earlier this year. I could play on a 1440p IPS, but I want more. I can't call it a need.
2, People, especially those doing machine learning, who need big VRAM. Similarly 7900XTX has 24GB. If that is "excessive" for 4090, then we shouldn't have it on 7900XTX either? Go against the "more VRAM" tide. You shall not have excess VRAM.