Verizon is better than T-Mobile as Verizon has better coverage and more reliable coverage than T-Mobile, especially in rural locations.
T-Mobile is a good cell provider and they tend to have faster 5G speeds in urban areas and a more generous perks package than Verizon.
But Verizon is the most reliable when compared to T-Mobile.
Although T-Mobile can be better if you're an urban dwelling person and want faster 5G speeds.
If you need the most reliable and most consistent connection across various locations and or you travel a lot then Verizon would be a much better choice than T-Mobile.
Verizon also has a family plan that allows you to select different plans for each line, which can also be more flexible for you if your household has varied needs.
T-Mobile though does have free in flight Wi-Fi and some other freebies.
Many of the T-Mobile plans also have the taxes and fees included, which makes the advertised price the final price.
I prefer Verizon myself as I get better coverage than I did with T-Mobile.
I also have Straight Talk Home Internet which is also owned through Verizon and it works flawlessly and it hasn't caused any issues.