This matter is now clearly getting high-level attention ... as it should have much earlier, even before CA sent forms 1099-MISC.

“IRS says guidance on whether Middle Class Tax Refund is taxable could come next week”

https://www.kcra.com/article/rep-kiley-calls-for-irs-to-issue-guidance-on-whether-middle-class-tax-r...

Of course, be care what you wish for!  The answer might not be what one seeks.