Can the manufacturer just stop your carrier service dead in its tracks because they 'Don't support the operating system on BB10 OS? What has that got to do with 4G/LTE services anyway? A phone is a phone...doesn't the frequency and Band determine that?
Manufacturer, no, once the phone is out of the factory they don't control what the carrier or operating system vendor does with it.
If you are talking about certain cell bands not working,, that is the thing with progress and advancements in tech. At some point there is so little use of an older infrastructure that supporting it or keeping up with security issues is not worth it. Plus new security methods and processing power for newer apps and OS simply make the hardware obsolete
For older folks this may seen really unfair and happening too fast because before computers and instruments in general got very advanced, progress took a while. I mean the land line phone lasted for a hundred years as the main communication device but the move from 1G to 5G in phones was 40 years, 3G to 5G was about 20, and now the 3G phones are obsolete. TVs, same thing, standard def TVs lasted a long time, but the HD TVs to 4k TVs and broadcasts was barely a dozen years. Kids born after about the year 2000 seen to take changing platforms ever few years with a lot less complaining LOL