[agust]

Blink was forked 12 years ago, and the size of the team behind Chrome is probably at least ten times the size of the team behind Safari. So yes, there are major differences between two, and it's not just additional advanced APIs like Web Bluetooth. WebKit is lagging behind in all areas and ridden with bugs.

[asadotzler]

I doubt it's "at least 10 times the size" and probably somewhere closer to 5X tops with a 2X core that's the realistic measure since those are the non-rotating folks with real expertise who make things go. That team is probably about the same size as Mozilla's which is also non-rotating.