You have that backwards. Housing can only be affordable if it's not a good investment. If it's a good investment, people will buy houses expecting to get much more out of it than just a place to stay.

Look at Japan, for example, where houses lose their value after 40 years. I pay cheaper rent in Tokyo than I ever did in even mid-sized American cities.

Both of these are wrong because they confuse buildings and land. Land can be a good investment even if shelter is affordable. My understanding, for example, is land in Tokyo is quite expensive.

Random, but what do you do in Tokyo? I’ve been trying to break into their market for two years. Had an offer rescinded from Rakuten because immigration shut down.

The housing market boggles my mind how houses don’t appreciate at all there.

Houses are like cars. Nice when they're new, but problems accumulate over time, and eventually with the march of technology and fashion, no one wants an old beater if they can afford otherwise.

Why the downvotes? Housing can’t increase in value faster than real wages over time without making future generations measurably poorer. Of course, caveats apply. It’s reasonable that land prices in urban areas will on average grow as the population does, but if no development is allowed to be able to offset those higher prices then essentially nobody benefits from that increase in value besides existing homeowners.

It an be if you're allowed to improve it.