I only have access to Android devices, so my claim likely won't extend to Apple. In fact, I've been told by a friend that Apple watches do in fact use the GPS signal to sync the clock. But as far as I know, they are the only ones doing that.
In general though, you need to look in more detail at what your exact configuration is and find out what you have misconfigured.
Having to set registry values to get sane syncing behavior is just nuts when, again, my cheap Casio watch - which possesses a miniscule fraction of the features of a modern computing device - can deliver sub 500ms accuracy with absolutely zero fuss.