Just want to note that this effectively doesn’t apply to Verizon because they already have such a rule, which was imposed over a decade ago as a condition of the 700MHz spectrum.
This means we already know such a rule works for carriers and we can apply it to the others.
I would generally agree with you, but in this case, Verizon has already been subject to such a rule for over a decade as a condition of the 700MHz spectrum. Verizon does offer subsidized/financed devices like the other carriers, it just doesn’t SIM lock them beyond the initial period.
Given this data point, I think it’s a good idea to expand to the other carriers.