Writers definitely possess their own talents, I don't think those are imbued by anyone else. But I said "cultivate", not "gift" or "grant".

Good editors do indeed cultivate talent. When I started my freelancing career, I obviously had some innate capability, but I worked with some great editors who really helped me to develop further. The same was actually true of some English teachers who were highly influential in my life.

Editors who don't see themselves playing an active role in talent cultivation are, I think, doing their writers a disservice.