How much the land is worth is only one of the parameters.
Notoriously, the maintenance cost for suburbs and their infrastructure is significantly lower than the tax they bring. Shouldn't that be a major point un tax decisions?
You have it backwards. Suburb infrastructure is expensive and the land pulls in little tax money by comparison. They're almost always a net loss on the city's budget.
IIUC the maintenance costs of suburbs is higher. Not sure if you meant that.