When I read these comments in translation I see that unyny has written "a river is a river, and a stream is a stream along its entire length".  This is not how most people in OSM map rivers and streams.   https://community.openstreetmap.org/t/rzeka-czy-strumien/125897/1 seems to be a discussion about this - I would suggest that unyny joins that discussion.
Best Regards,
Andy Townsend (from the data working group)
