A little white grease will do it no harm but it all depends the situations you flying in as if you In dusty environments then the crap will stick to the worm and actually is worse.
A smear of white lithium grease will do no harm but just a smear.
Hi, I found that a small amount of spray silicone on the worm gear works the best, this way you won't get dust sticking to it. I have used this on my previous Inspire 1, now use it on my Inspire 2.