As an individual, spread deposits across accounts or institutions to stay within limits [1]. There are account products that will sweep your deposits across other institutions in order to ensure full coverage. Fidelity's cash management account will cover up to $5M using sweeps [2], for example. Mercury has a similar product for business accounts [3].
If you're a larger business (>$5M cash equivalents on hand), treasury management in government money market funds instead of a demand deposit account. All roads lead to mostly US treasuries here.
[1] https://www.fdic.gov/resources/deposit-insurance/brochures/i...
[2] https://www.fidelity.com/why-fidelity/safeguarding-your-acco...
(previous comment on the topic during SVB failure: https://news.ycombinator.com/item?id=35171289)