That's a good thought experiment: how would you feel @MrsSchrute if the government very suddenly (6 months notice) introduced an additional 20% tax on all mortgage payments, in order to fund improved state social housing?
Mortgage is a similar proportion of people's income as fees (so 20% of it is significant but usually not impossible... by giving something else up). It's similarly targetted at a luxury which only privileged people have. It's similarly hypothecated to fund something which most people are in favour of: but which costs the state a lot and so is underfunded and has limited availability. This new Mortgage tax is really very similar to the new Education tax.
How much is your new tax? Could you find an extra 20% on top of your mortgage? What would you have to give up? How do you feel about it?
But now -to make it more similar to Labour's education tax - imagine that whilst you 100% pay your mortgage payments, the government 100% pays for social housing for anyone who doesn't have a house. So as people decide to give up their house and mortgage - either they can't afford the extra 20% or it no longer seems worthwhile - the government has to start paying for their housing. Inevitably, existing social housing is under strain. The government must either squeeze more peoole into the existing flats or use the money they had earmarked for improvements to build more housing. So despite the 20% tax, social housing no better.
Oh and some people who had adapted their own house for disability (at their own cost) but couldn't afford the extra 20% are now housed in unsuitable housing with stairs. After it has been utterly shit for them for about 2 years and their mental health is shot, the government will pay for an incredibly expensive jetpack for them. The person would have preferred to stay in their own, adapted home all along.
You're paying 20% of your mortgage extra tax, but no one in social housing is better off. Some people are much worse off. It's a complete shit-show.
Still happy with it?