Of course inflation brings in revenue. You get inflation when the government prints money (electronically, these days) to "do stuff". It's no different than a tax on any account you hold with that currency.
And inflation allows the government to make money off of any asset you hold, too. Let's say you buy a brick of gold (or equities or real estate - doesn't matter) worth $100. In a non-inflationary environment, you sell you brick for $100 ten years later and... nothing.
In an inflationary environment, you sell your brick ten years later for $1000. From the government's perspective $900 of that is profit for which you'll have to pay income taxes, even though the purchasing power of $1000 is the same as it was when you bought the gold. If your tax rate is 30% that's a $270 tax payment, and the government has managed, through inflation, to take 27% of the value of your gold brick.
Inflation is a wealth tax. Always.