Because the GST only applies to new homes, at the end of the day it's basically a construction tax. There's no real difference from a development charge.
If you remove $50,000 of taxes on a new home, that makes it easier for families to qualify for a mortgage or save up enough for a down payment. It's important to get those taxes....
You're absolutely correct that it is across all three orders of government when, for a modest three-bedroom in London, Ontario, the construction taxes have gone up 600% in 20 years. I think we need to look at reducing those back down to more manageable levels.