“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.
Friendly reminder that 5G service availability in the US is still dogshit and often incurs packet loss which you can mitigate by disabling 5G which forces your device to operate at 4G/LTE which has a superior range.
Of course they could have set a software preference for LTE over 5G when PL is detected, but that advanced technology used by literally every other multiband radio standard is too complicated for billion dollar OEMs and service providers to implement.