I don't know. Most finance people now have access to bitcoin exposure through trusted institutions via futures. Many of these people felt a lot of FOMO at missing the boat on Bitcoin's last big jump. I think if it drops to $5k, there will be some big players taking a long position in hopes of another order of magnitude movement. Certainly could get much uglier, but I think Tethers vanishing would not be fatal.

Also, with Bitcoin becoming 'established' I bet everyone who owns more than $1M in cash is considering Bitcoin as a method of alternate banking and transferring funds internationally.

Bitcoin certainly isn't the safest place to store your money, but there is a decent argument to be made that it can be safer to keep 90% cash and 10% btc instead of just 100% cash for some risk profiles. Criminality is one obvious use case, but people who want a plan for how they could flee their country in the case of disaster, financial meltdown, or social unrest would also see advantages: much easier to get a $100k private key through an airport and customs than the equivalent in physical cash.