But you've just contradicted yourself. It's fine to take a risk with a mortgage and a noose around your neck if we have a repeat of the 80's with interest rates going into the teens and then you say don't do it with a car which if devalued would't exactly bankrupt you like a house! It's all swings and roundabouts. If we follow your archaic idealogy then the 75% who have mortgages should rent because they can't afford to own outright. The reason we got into the 2008 crisis was with sub-prime lending on Mortgages nothing to do with cars or other luxuries on finance.
The sub prime crisis was just the straw that broke the camel's back. The total story was simply a mountain of debt that the world had built up and most asset classes and most people were collectively responsible.
Back on message, the 'if it goes up own it and if goes down rent it' story is itself an over simplification. The reality is just a mixture of people trading off value for money, flexibility and time to get what works for them. Cars don't depreciate less if they are leased. Sure manufacturers' often offer cheap deals to meet targets but you can get these through purchase consolidators as much as through leasing companies.
Nothing wrong with people moving to buying everything on a price per month basis but it doesn't mean it costs them less. They get more 'utility' (it's a sugar thing) but in the round they pay for it as finance companies have to make money to offer to bankroll people paying for things monthly rather than upfront.