U.S. has had periods of deflation:
https://www.usinflationcalculator.com/inflation/historical-i... .
As recently as 2009.
Not exactly the strongest counterexample I've ever seen, though (barely) technically correct.
And the last deflationary "period" (a single year) before that was ... drumroll... 1949, following 3 years of >8% inflation.
0. https://taxfoundation.org/historical-income-tax-rates-bracke...
1. https://www.taxpolicycenter.org/taxvox/effective-income-tax-...
On average, aka the vast majority of tax revenue, it's stayed constant according to your own source.