This is mostly correct.
Not all Teslas can charge at 48A. Model 3 SR (including SR+) is limited to 32A - see
Wall Connector. (SR+ is not listed on that link but you can see it in the specs portion of the Model 3 page)
The wall connector can be on a circuit UP TO 60A, not just 60A. Not all houses have enough spare capacity to allow a full 60A circuit. Again see the link above for how many miles you’d get at lower levels.
Also, keep in mind the wall connector uses 2 conductors and 1 ground - 14-50 uses 3 + 1 ground. So the wire cost is different for each. That and the difference in cost of a GFCI breaker can narrow the price difference.