Sure, but that's not what people talk about when they talk about 'wealth tax;' the accepted definition is net, not property.
As proof, if we already had a wealth tax and people referred to it that way, the past year and a half wouldn't have had people arguing over whether or not we should introduce a wealth tax. It would be whether we should expand the wealth tax to cover new assets.
Also, I think it's quite common outside of the USA for property taxes not to be based on the current market price of the property and also not to be charged at a fixed percentage of the value, both of which make them rather different from any proposed wealth tax.
Many meaning 7, right? 7 countries have net wealth taxes.
It used to be many - dozens of countries did it. They stopped doing it.