This is one of the hardest things to explain to people.

Here is a thought experiment. Lets assume that the minimum required to live in a given place is $20K.

So now you have two people, one makes $30K, the other makes $40K. How much more does the second one make compared to the first? Twice as much. At $30K, you have $10K disposable. At $40K, you have $20K disposable. And someone making $60K is making four times the disposable compared to $30K.

Once you get above cost of living, everything gets easier.

When we were looking for an apartment between selling and buying houses, I was surprised by how there is a decided floor to rent prices. Like nothing exists below a certain point. Somehow I felt we could just get a super cheap place because I thought housing price would scale with income. I was surprised when I found out it didn't. So your cost of living example holds up in my experience.

That's the result of housing shortages. Landlords can pick their tenants and since they don't run a charity they usually rent out to the highest bidder. The obvious solution would be to increase supply.

Yea. You can get $240k in debt.

Good luck getting anyone to lend you that kind of money if you're actually poor.

Someone who is able to get deeply in debt basically by definition has access to money. They would not be granted loans otherwise.

the largest portion of my debt was student loans (over half), which anyone can get in the US (not sure about other countries).