Looks nice but it's probably not really usable for navigation. I checked the Netherlands and Germany. You'd need more details for safely navigating on the water. But it definitely has potential.

There are also some other specialized open street map based maps for

- rails: https://www.openrailwaymap.org/

- cycling: https://www.opencyclemap.org/

- sea map (competes with this I guess, and is a bit more detailed for navigation): https://map.openseamap.org/

And probably loads of other ones.