> Roku would have needed 8000 bank accounts to hold their cash at 250k per account.
No. Roku would have had to use one of the many other methods to mitigate the risk. They could buy their own insurance, for instance. There are options.
It isn't a new phenomenon that companies have to handle more than $250k at a time, and companies have been managing this risk though a number of different mechanisms from long, long before silicon was anything other than sand.
If you had a company and were keeping large amounts of money deposited without any risk mitigation, that was a choice. Or that was you winging it without competent financial advice. Either way, it was a risk you were choosing to take.
> You are basically telling businesses to not use the banking system outside of the too big to fail banks
I'm actually not, because the same risk exists with those banks, too. It's less likely, perhaps, but it's not zero. Just like it wasn't likely that SVB couldn't pay out to all the depositors, but it wasn't zero.
No matter how small the risk is, if you roll the dice enough, sooner or later you will get bit. That's the nature of risk.