From 2007 to 2008, for example, global wealth declined about ~10% [1].
There's not much room left for central banks before we officially enter banana town. If cyrpto implodes, it could easily be worse than the financial crisis - which means, regulators have an interest in it NOT imploding.
[1] https://www.credit-suisse.com/about-us/en/reports-research/g...
As an example, I have 5-20k in crypto assets on any given day. My wife and I are also shopping for a new couch. If my crypto assets evaporated we would not be shopping for a new couch, nor would we be going out for dinner tonight, despite the fact that I am not spending down crypto assets to fund either of those purchases. The psychology behind it is that people adjust to a certain amount of "savings" and will adjust purchasing to get back to that level if their savings changes quickly and substantially.
https://www.barrons.com/articles/a-new-crypto-etf-is-here-yo...
I have a hard time imagining what actual tangible disasters will happen if crypto currencies lose their value overnight besides some speculators losing money and some mining centers closing.