Second it's a fairly know issue that the way creditscore is established is pretty flawed. You can have 10mio on your account, but if you have no job or own your own company it will actually affect your credit score. This whole thread is started because of some of the issues.
With regards to the debit card the point is that the kind of purchases you did before you got a credit card, aren't going to change dramatically or fundamentally after you get one.
That's not true. Your FICO score does not take into account your employment status, nor your income.
> With regards to the debit card the point is that the kind of purchases you did before you got a credit card, aren't going to change dramatically or fundamentally after you get one.
If that were true, it would contradict your earlier argument that "most people don't use it like that which is why it's such a good business." Your statements cannot both be true.
First of all, you can have an excellent credit score without paying a penny of interest. All you have to do is buy things with your credit card, and pay the bill in full when it arrives. You will never pay any interest when you do this.
Second, the people who measure risk for a living have determined that people's history with small amounts of debt is indicative of their ability to manage larger amounts of debt. Do you think their actuarial models are incorrect, and if so, why?
Furthermore, it's not like a good credit score is all it takes to get a mortgage. Proof of income matters too. As anyone who bought a house since the 2008 debacle will tell you, mortgage lenders take great pains to verify borrowers' income and the source of the money they use for their down payment.
> You could instead just look at the history of their debit card usage to figure out whether they are trustworthy.
No, you really can't. A debit transaction is a direct deduction of money from a checking account -- it is not debt. The only thing that can go wrong is an overdraft, and even when that happens, the payee will probably be unaware of it. Debit is more similar to cash than it is to credit. People have very different psychology and behavior when they use debt instead of cash.
There are plenty of problems with the credit system in the US, but the things you have identified as problems are not real problems.