Preventing commercial use is still a major argument used.
Previously, in the 1980’s, yes I could see a Taxi/Plumber/etc using amateur radio equipment as a cheaper workaround for their business, but now it’s so much cheaper (and better) to use cellular or, if you really needed business radios they aren’t crazy expensive as they once were.
However, as an ham radio license holder, I would still not want to see our amateur radio frequencies, which are purposefully set aside by the FCC for hobby and experimental use, used for any commercial purposes at all.
Commercial radio has its own spectrum and rules, and the cost to use it is not insignificant. Many businesses in my area still use radio because it is more reliable and controllable than the services provided by mobile operators. A lot of these would absolutely jump at the chance to use the ham bands and ditch their expensive commercial equipment, regulation, and fees if it were legal to do so.
For non-local communications, HFT companies have been looking at the HF bands for years to shave a few milliseconds off their micro-arbitrage transactions (compared to wired networks) and ham radio has the largest chunk of spectrum after the military.