It's called the ratchet effect. The government doesn't like giving your money back. That's why taxes almost never go down, either - e.g. the "temporary" income tax that only affects the richest 1% of people..
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.