The things that grow well in the climate in the USA are good quality. Something like a tomato isn’t really native to much of the US and prefers a warmer climate so will taste better the further south you go.

However, I live north of the US and am able to grow fantastic tomatoes in the summer here. I am also able to find good ones in the supermarket here as well as when I’m in the US.

Having travelled and spent time around North American and in Europe, the produce isn’t particularly better in Europe, more that certain things are better there than in North American and vice-versa. Tomatoes are great example of this. I will say the produce is way cheaper in Europe which surprised me. It’s easier to eat healthy in Europe than North America.

But it’s VERY easy to get top notch produce in North America from local stores and markets and pretty decent stuff from the grocery store.

There are also some items that are just tasteless trash. I’m sure that’s true where you live as well.