This essay doesn't address any of the key problems often raised when talking about AI and UBI. Here is Australia we are already seeing one the effects of very cheap stuff. Skilled labor is significantly more expensive than buying things, so anything that has to have an Australian involved is ridiculously expensive. Calling the Plumber to fix a drain? That's a week of groceries or perhaps a new TV. At some point soon…
I'm not sure what you're referring to here. Taxing land doesn't really have much connection to farming specifically. In fact, most high value land is urban areas and cities (NYC, SF, Silicon Valley, etc.), so farm land is mostly irrelevant when talking about a land value tax.
> Any aren't we supposed to be reclaiming land to turn back into national parks, planting trees, and capturing carbon.
To do so, we need to use more land more efficiently: less sprawl, and more building up/dense. And a land value tax incentivizes precisely that, since in high value areas, the tax would be high enough that it dense buildings would be the only real financially viable option. This increase in density in the core means we don't need to develop other land (and even reclaim some of it to parks as you suggest).