Definitely sounds like a USA specific issue. In Australia we pay for GBs data, it's up to us what we use it on. I'd be appalled if they tried to pull that bullshit here.
Most carriers include 'unlimited' data, usually broken up in XXXGb at full speed, then unlimited data at much lower speeds.
While I hate subscription models, I actually paid the yearly subscription for this (fyi $27.99 in Australia.
One of the main reasons I paid is because I used Sync for Reddit multiple times a day for years and wanted to support the developer. If the fedeverse fails to take off at scale I won't renew for additional years.
$28 is a small price to pay on my behalf to thank the developer for all his previous work, but also support further development. It's high quality apps like this that help drive traffic to the excellent communities that are reestablishing themselves in the fedeverse.
It's a rather sad state of affairs. I have 2 accounts, one for professional network and SFW interests, plus another for porn. The professional network and SFW interests has become an absolute bonfire. I find myself using it less and less. I used to check every day, now I barely check once a week.
TL:DR Twitter is only useful for porn these days, and even that isn't fantastic.