Comment by jdranczewski

I've recently found out that this is not quite true - while the primary purpose of their tile servers is mapping and editing applications, they do allow third party apps to use the servers as long as they follow usage policies: https://operations.osmfoundation.org/policies/tiles/

This recently came across my radar as Home Assistant has migrated to the vector tiles hosted directly by OSMF for all deployments: https://github.com/home-assistant/frontend/pull/53816

For my own needs I usually just go for https://openfreemap.org/ though, I like the default style, and it feels maybe a little faster.