A Georgist LVT is based on the value of the bare land, which is constrained by permitted uses. Adopting it without first removing zoning restrictions would increase the incentive for homeowners to defend the existing zoning rules, since the removal of the rules would increase the scope of alternative uses of the land in ways which would make it economically impossible for most existing single family homeowners to afford the taxes on the property.
On the other hand, once you remove the zoning restrictions, the existing economic incentives will produce densification without LVT, tbat's the whole thing the zoning restrictions exist to stop.
I mean, I agree with you about zoning; we're fourth and inches from eliminating SFZ in my muni, and an LVT isn't going to happen anywhere, so the rest of the debate is kind of academic.