I was about to comment something like this. Consumption from a VAT perspective doesn't increase linearly with wealth, so a more wealthy person isn't going to spend and get taxed via VAT 100x more than someone with 100x less wealth, and VAT affects the poor much more than the rich because it's a tax on consumption irrespective of wealth, so the poor pay a larger percentage of their wealth to VAT.

We should just get rid of VAT and replace the lost tax revenue with something that's more equitable, such as a proper wealth tax. It's not like wealth goes away with a UBI.