I've been with T-Mobile for about 5 years no and am very happy with it. We're on the unlimited over 55 plan, no taxes, no fees, unlimited text, voice, and data for $30 per phone per month. As a result of being a T-Mobile customer, I also get $10 per month off my monthly YouTube TV bill as well as a free subscription to the streaming MLB service every year. I get free text and data when traveling out of the country although due to the pandemic, I've not used this benefit for a while.
My only complaint is with their coverage. When traveling by car in the US, it does seem like T-Mobile's coverage is weaker than Verizon's. In some rural areas, we'll literally have no signal, even when on an interstate, so depending on where you live/go, Verizon may be a better option.