Like the title says, razorflies damaging and killing enemies doesn't count towards %dmg and kills on the game statistics, so to the team it's always like you're "contributing less" than you actually are. (in case you don't know) Their damage is enough to kill lvl100 armored grinner in seconds, if Diwata is built with mods that benefits them, of course. So yeah, it could be considered a core Titania ability to deal damage, but the game completely disregard it. (I know "%dmg" isn't everything, but it helps with ppl complaining less.)
Interestingly enough I just noticed today that Razorflies kills ONLY counts towards your own when playing SOLO/Hosting. Which is weird because DE has the "know how", but decided it just doesn't work as "intended" when playing with others. Also, I've previously searched and found people never talked about it, guess not many main plays Titania.