In the US, almost no one buys their phones outright. They "lease to own". Anyone whe does buy their phone outright can just buy the unlocked ones.
So I'm not sure what this rule would actually change. You're already not Carrier locked if you bought your phone. You're only Carrier locked if you lease it.
The big fuck up was eliminating competition by allowing t mobile to buy sprint. Too many pieces of shit were in charge 2016 to 2020.