With Dogecoin and friends we're entering scam territory. But really I was curious because it sounded like the GDC7 was suggesting there were multiple trillion-dollar scam companies. The reason I commented was that while I think there are a lot of ridiculously valued companies, I'm not so sure we can consider many of them a "scam".
We could bring up a million shitcoins and scams but then we'd be here all day.
If you really want to chuck a hand grenade at the crypto-cultists ask them to rationalise Tether.