I could not find where it says 99th percentile in the US is $1M, but it seems unreasonable based on recent run up in asset prices, especially homes. The median home price is north of $500k in the western US.

https://cdn.nar.realtor/sites/default/files/documents/ehs-04...

Come to think of it, I wonder if these net worth calculations incorporate present value of annuities such as Social Security benefits and defined benefit pensions.

That report might well be out of date. It's a year old, and possibly based on data from a year (or more) prior to that. I don't know.

My more general point is still true though - it's the people with 100s of millions who have the resources to minimize their tax burden who could (note: I'm not saying 'should', that's a matter of opinion) be paying more.