The kind of unlocking at issue in this case refers to a) unlocking phones that a customer owes a balance for or b) unblocking stolen phones (which are blacklisted by carriers to deter theft).
The market is offering people the choice of locked and unlocked phones. Everyone can make their own choice. The government already requires the lock to be temporary.
So then banning phone locks is the same as banning people from being able to exchange their freedom to use a different mobile network for a lower purchase price.
US networks can also choose to advertise unlocked subsidized phones. The fact that they do not at a sufficiently competitive price to locked phones must mean the lock is worth having.
The law is not forcing only two options, the market is. Any lender can lend money for a phone, just like Canadian mobile networks do.
Plans are far more expensive in Canada,[1] so I'd be very surprised if phones are not also more expensive.
In the past five years I've benefited from three very attractive Sprint promotions:
* 2017: Through Best Buy, offers amazing iPhone SE deal to customers. <https://np.reddit.com/r/NoContract/comments/6lyjyl/cheap_pre...>
* 2020: Used iPhone 8 for $99. I buy one, sell the above iPhone SE for a profit. <https://np.reddit.com/r/Sprint/comments/hl1qu3/my_experience...>
* 2022: New iPhone 13 for $200 plus trade-in. I trade in the above iPhone 8 and will pay $6.67/month for the following 30 months. (Had I chosen the iPhone SE v2 I would not have paid anything.)
I am very, very certain that none of the Robelus has ever offered an iPhone for anything like any of the above, let alone all three.
[1] Canadians who have a US mailing address often choose to get US plans with Canadian roaming service, because doing so is cheaper than getting a plan from Robelus.