Every carrier is the same: They offer a service and try to make money. A carrier is all parts of service, sales, products and the people who control and work for that company. Every carrier has fine print, has CS reps that work on commission, or work for multiple calling center clients who may or may not know the ins and outs of the company they represent that day. They all get their product from the same manufacturers, for the most part.
What is also true is that most all carriers have similar coverage in some areas, but not all carriers have the same coverage in every area. Yes, most are priced within $5-$10 of another carrier's rates. All of them offer similar phones and devices of same brand or capability. It comes down to the "perks" offered by each.
One must choose in this day and age their network based on where they use that network, as the differences seem to be becoming similarities nowadays. All will have a deal on this phone or that plan, but the difference in price will be made up somewhere, since sophistry is how the game is played. (cheaper phone/higher rate, cheaper rate/higher device cost) (Sprint offers 50% off your data, but if you had a $50 T-Mobile plan and switched to Sprint, you'd pay $25, BUT then add on the $20 access charge....you save $5, but coverage might be limited)
Even data seems to be an area of word-play, since T-Mobile offers unlimited high speed data to a cap, then unlimited slow-speed data and offers free video streaming at a reduced quality and free music streaming, and Verizon offers unlimited high speed data to a cap, but offers no free data via reduced video quality or free music streaming, but does offer unlimited slow-speed data. (T-Mobile limits video quality, but doesn't charge data on some plans for video, but Verizon does NOT reduce video quality, but DOES charge data for video)
See what they did there? One gives free data usage, but limits the quality. The other does NOT limit, but you are reduced in the amount of data you COULD use by NOT reducing consumption via quality reduction. Sprint makes back that 50% reduction in switching costs by charging that access fee, which is ALREADY part of T-Mobile's plans since they don't separate the line and data fees and instead, call it one plan.
In the end, they are all making money and all have good and bad fine print and CS reps.