I think they changed “loving kindness” to “loyal love” throughout the Hebrew Bible, it was not peculiar to this verse. Personally I liked “loving kindness” better but maybe that is just because of familiarity. It was in the kingdom songs and everything: “his loving kindness will follow me”, and so on. I guess they’ve probably changed the lyrics to the songs too.
What I never realised as a JW is that the phrase “loving kindness” is very prominent in Buddhism. I don’t know if the GB is aware of that or if it played any part in dropping the phrase. Probably not. It seems just an attempt to replace a particlar idiosyncratic translation of Fred Franz with something that is more understandable and perhaps closer to the original meaning.