I have T-Mobile. They throttle hotspot after a small amount, i think its 5gb. With the app I use it hides the hotspot from the carrier, and even Microsoft (which stops it from auto restarting updates). So to the carrier im just using my unlimited cell data alot.
It's janky though and can cut out at any moment . Sometimes it'll stay connected for an hour, sometimes i have to reconnect every few minutes. But it's worth it, i can dl games and stream movies.