Neither. Above poster is wrong. You don't require anything to own a house or car in the US except your own cash/equiv. If you wish to borrow other people's money or property (in some cases at all when counterparty risk is high enough or buyers competitive enough, in most cases it's more a matter of interest rate), a sufficient credit score is the most standard and easy way to "make the case" that you will repay. But that's truly not at all required. I bought my current truck for $8100 cash on the table, I just showed up at the other guy's place and inspected it and chatted, looked good enough, paid him and we did the title change document, I screwed on a new plate and off I drove with it. Effectively zero dealers will not accept cash upfront. You can buy land and just build your own place.
Obviously, a lot of us find having credit very useful. And it's also both convenient and good for fairness/economic velocity/efficiency not to generally have to explicitly put up any extra collateral to get it or go through some complex old fashioned social dance. Hence "credit scores" that systemize a lot. But claiming they decide "whether you're allowed to have a house or a car" warps things badly.
Like if you're arrested for some misdemeanor, that goes on your social credit score. If you're caught peeing in public your social credit score basically goes to zero (registered sex offender).
(Genuine question, I'm not American and don't have any desire to move to the US).