So if I want to maintain a one story building on land that is zoned for a 40 story building, I have to pay extra taxes even though I'm not using extra services? Seems to me like the best policy would be taking both into consideration.

Yes, because that's the land's actual value.

This is why land-value taxes are unpopular: small landowners (e.g. Mom & Dad) want to be able to hold onto their small single-family homes instead of being forced to sell to a developer who would build a multi-family dwelling.

Cf. Prop 13 in California.

But why the insistence on taxing land at it's full value while ignoring what's on the land? High taxes on just the land force me to sell and to improve the property. High taxes on just the house can force me to not improve. Neither seems ideal. What would be ideal to me is a good balance that rewards improvements without punishing those who don't want improvements. Especially if the owner lives there.

You're thinking like an academic in a glass tower and not a real human.

You wouldn't buy the property unless you had plans to develop it into something. Unless you're the kind of fool who buys 128gb RAM and only uses 4gb of it.

The price of an item should reflect it's use and probable ROI.

I own and develop property. Who looks like the fool now?

Please keep it civil. Hacker News is not the place for put downs, two of which you've included in your short response.