I note these are mostly US-specific reasons, but the property bubble has been a thing all over the world both now and pre-2008. It's a phenomenon of popular cities everywhere.
You make it sound like a bad thing? Policies should favor the people. There are policies that favor renting flats too.
I believe the problem is not "making it a good deal to own your home". That should be the default anyway.
In China for example there's no property taxes and you can't send your kids to public schools unless you own property.