Fellow good accent, poor grammar haver (but in Czech) - hello! I agree completely. In fact we are not alone, here’s a video where a YouTuber is praised for his use of English (including contemporary idioms etc) in comparison to someone who has a good accent but comparatively poor command of the language itself: https://youtu.be/-81TSnMUA68?si=4j4mxiSssnQIBVRq

Personally when it comes to speaking English I find a false American or English accent quite unnerving.