I loaded your data into ArcGIS Pro and overlaid it on top of another water map from ESRI (it’s much smaller, but more accurate). Looking over the map your rivers and lakes were quite accurate with reality. But something anomalous was happening in the Siberia area. For example, here is a screenshot from Western Siberia, in the region of many lakes and rivers that flow into the Ob (coordinates on the screenshot). The blue and green are data from ESRI (which I checked on google maps and others), and the Purple and yellow are yours. The lakes are in their proper places, but the rivers are just in a pile, no logic. You can clearly see where there are no lakes in the narrow white areas - there is a river running there, but your rivers don’t reproduce that. I’ve only checked this case so far, but maybe it’s like this everywhere in the subarctic regions.
I can’t show pictures for some reason, so here is a link to my google drive with a folder with screenshots:
https://drive.google.com/drive/folders/1twy1iR1PAhhu6VnhU1ZaBtQkZLhnF86d?hl=ru
