That claim makes absolutely no sense. Taxes are revenue the government brings in. It can then use that money to do stuff. Inflation does not bring in revenue, and does not make it possible for the government to do stuff.
If 10 citizens each have $10, then there are $100 in the money supply. Now the government prints $10. If no actual value was created with that $10, then the value of the dollar has to drop. Now all the citizens have $9.1 (real value) and the government has $9.1 (real value). This is the same as a 10% tax on wealth.
Cliff's notes is that quantitative easing is really money printing used to finance government spending, and is really just another form of taxation, although it goes through a slightly convoluted process to get there.
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.