This proposed law replaces the existing one, there's really no ambiguity about that.

In the current system you're taxed on a fictitious return on investment (e.g. a 30% tax on an assumed 4% return on investment gives you a 1.2% "net worth tax")

In the new system you're taxed on the "real" return, which includes paper gains. That's mainly a problem because you have to rapidly liquidate assets as they go up in value. While on the way down the government just gives you a voucher against to future taxes. For a limited time. And can't be used to offset income tax.