“T‑Mobile will never change the price you pay for your T‑Mobile ONE plan.” That was the promise. The Un-contract. The whole reason millions of customers picked the magenta team over Verizon and AT&T in the first place. Now T-Mobile is retiring legacy 3G and 4G-era plans — Magenta, ONE, Simple Choice — and automatically moving customers onto “modern” 5G plans at higher monthly costs. Billing changes hit mid-July for the current wave. The company that swore it would never surprise you with a rate hike just sent the notification.
Inflation. You can be confident that these guarantees won’t last unless not only are they in writing but they are backed by independent financial insurance. Same with any life membership. It is very unlikely that they are actually charging enough to continue the service for life and so they are likely going to be forced to do something about it at some point. Often that something is bankruptcy.
Still, it sucks.