You would sell the development for as much as you can get, regardless of tax. The people buying from you aren't going to pay you more just because the government raised your taxes.

A land tax would effect every single landlord though. Every single landlord would put up rent.

The market will bare it because people have no choice. The choice is homelessness or paying the higher rent.

It's principally the same when mortgage rates rise. Landlords with mortgages put up rent. Only it would be worse, since not all landlords have mortgages.