Why is a weak signal or no service happening only in the US?

AT&T keeps wanting to blame weather, geography, building materials, and anything else they can think of as the reason why we get a weak signal, or worse, no signal (emergency calls only). Curiously enough, these issues don't crop up in Europe and Scandinavia. Why is that? I have yet to lose service or signal strength when i'm in Europe but for the life of me, i can't complete a call when i'm driving down a heavily trafficked state road in western NY (where it's flat terrain and no tall buildings). Yesterday, i was trying to speak with my son in Syracuse who is also with AT&T. Our call dropped over 10 times! He was sitting in his top-floor apartment while i was driving through open fields between Rochester & Buffalo. No excuse for such craptastic service! It was a simple phone call, no data-transfers, not watching Netflix, not trying to play video-games; just wanted to have a good old fashioned phone conversation. And they're talking about 5G? Give me a break!! Please fix the most basic services first before you try to reach the moon.

I honestly don't know why i am still staying with AT&T! I am so angry and fed-up with their excuses.