Debt is a huge facilitator of price increases. Easy debt due to usury has been known to destroy societies. It's not for no reason that it's prohibited in Islam, Christianity, and Judaism.
Just because some people refused to follow their texts, doesn't change the facts that it is prohibited in them. Jews still refuse to lend each other money with interest.
Again, just because those Christians and Jews refused to follow their texts, doesn't mean that it isn't prohibited. The Quran documents and confirms this fact: https://quran.com/4/160-162
We spoke to them and they admit it. Furthermore, we're not asserting "religious dogma" by simply reading their books and calling them out on not following them.
In your same example:
I have $10k, and buy that $100k house with a $90k mortgage. For simplicity let's forget mortgage repayments
After 10 years I sell for $163000, leaving me $73k for my next down payment
I can now "afford" a $700000 house assuming banks are willing to lend 90% LTV