The issues I see with a transaction tax is that it incentivizes lower velocity and/or system skirting. We already have transaction tax on Bitcoin, and we "skirt" that system by making a "joint account," if you will, and making off-chain transactions that don't get taxed, then settling later. The same thing will happen on new layers. It may also create an incentive to use custodial wallets that will reduce the number of "taxable" transactions. A flat tax is a lot more doable and less "skirtable", and the same goes for property tax. I wouldn't mind taxes if they're quite small and I and my neighbors can talk directly to the people who decide what it is. If I don't like it, I can move outside the city or county. A national tax however... not so much.
Again, #localism