a) Like Japan's lease law[1], it would be possible (and preferable) to limit lease periods
b) As I pointed out at the start, someone else can buy the land at at a very low price.
> However, if someone bids on the land for that price you must sell.
So even if you follow that avoidance strategy, I'm going to buy your land on the cheap. Perhaps I'll have to raise the tax in the meantime without the comparable rent coming in because of the lease agreement you set, but I get your buildings at the end so that's basically become a mortgage.
Of course, that possibility could be removed by a rule like having a period where a lease is in the offing where prospective buyers can buy and cancel the lease, punishing those setting low rates.
Still, I think this a digression, it's hardly a steel man, which would be more interesting. We may as well say that income tax is rubbish because people can lie to the tax man about their income.
[1] https://resources.realestate.co.jp/buy/leasehold-rights-in-j...