Uhhh....yikes. That sounds like collapse...the exact opposite of what's happened the last 5 years.
Actually, J. Allaire of Circle did refer to 2.1 quadrillion satoshi or [units] in several public speeches.
Besides, with 21 trillion units you can start working toward unity(equality) with $$ since high tens/~hundred of trillions is where world GDP is.
Why would this be a collapse-no, instead of artificial scarcity it would be seen as an adequate number of units and we will work from low value per 100 satoshi to higher.
I can predict that this alone will cause a dramatic increase in activity because people will perceive having much more [units].