Earlier quoted context omitted.
> Today, you pay very little tax on the empty land or parking lot because you’re taxed on that total value of the land and improvements. This discourages building stuff sometimes. With land value tax, you’d be taxed on what someone would pay you for that land with improvements similar to surrounding, so it’s advantageous to build something there instead of nothing, since you’re paying the same tax as the sky scraper…
You're looking at it the wrong way. They're not looking at the hypothetical improvements and charging as if you built them. They're saying "this land could reasonably support a skyscraper, therefore it is very valuable land".
If you implement a land value tax, as I understand it, the parking lot and the skyscraper next to it should be taxed the same if they have the same footprint. All things being equal, that means a very large tax burden for the parking lot owner, and that certainly is an incentive to transfer it to someone who will do something with it, which is what you're advocating for.
But at the same time, it makes the price you can get for the parking lot much lower. And I'm having a hard time not equating sales price and value. And once I've seen that under a LVT, the parking lot has no or little value, because it can't be sold for much money, it's more confusing --- if the value is low, and the tax rate is based on value, why are the taxes so high?