Building/converting more businesses that accept and hold on to their bitcoins looks to be way to go.

There are other solutions that can help accounting. To avoid a tax event while selling, taking a loan against Bitcoin on Sovryn defi running on RBTC might be a viable option. Obtained stable coin still needs offramp though. Risk is comparable to the tax that would be paid in the long term.

But realistically I think other banks will take place of fallen crypto friendly banks. Besides, it is not difficult for prominent Bitcoin companies to start their own bank or buy one.