None of the SVB customers signed up (or paid premiums) for unlimited depositor insurance. Nonetheless they will now receive that, paid for by a new assessment (tax) on other banks and their customers.

They expected (with 99.8% confidence) to be able to retrieve their deposits in full.

So the 0.2% scenario is turning out different.

If insurance company had assessed the risk as 0.2% the premium would have been miniscule. But they still didn't pay it, or the risk was not 0.2%?