I really think this modification could definitely help extend the life of your grabber claw on your Chasing M2. RC Car and boat hobbyists use Plasti Dip all the time to seal off their circuit boards like a servo and receiver. The problem is with any type of electronic that goes in the water, with time rubbers gaskets can deteriorate from salt or long time use in even freshwater. Even when the grabber claw is picking up heavy items off the bottom, the claw's shaft can bend a little and cause leakage at the gaskets. It's already happened a few times with both the Chasing M2 and Fifish V6s grabber claws.
What's nice about this liquid rubber in a can particularly is it doesn't leave any sticky residue behind like Flex Seal or Gorilla Waterproof Patch & Seal. I looked at the competition and they all seem to leave a sticky or permanent mess behind which you don't want, I even considered Flex Tape but it seems that's more of a permanent solution reading the reviews. The reason you don't want to leave any residue behind is none of these products stay on permanently, they eventually start pealing away, so when that happens you don't want a sticky mess left behind. Plasti Dip is one of the first liquid rubbers in a can that car hobbyists used on their car wheels to give a nice looking black coat, any time they want to take it off due to a rock chip, it would peel away very easily and then you'd put a new coat on no problem.
I already put on a first coat of Plasti Dip on my own Chasing M2's grabber claw, I plan on putting on a second coat soon. I'm just the type of guy that tries to think ahead when extending the life of my underwater drone and its parts, most underwater drone owners tend to use silicone spray to extend the life of their thruster motors, I could see Plasti Dip also being a very popular product like silicone to extend the life of the grabber claw, as sort of a maintenance.
And personally I'd use the dipping can version, not the spray, that way out get a thicker coat and use some cheap paint brushes to apply it on very specifically to the seams and around the screw holes, then once it dries, think about applying a second coat. And make sure you buy the black colored Plasti Dip, not the transparent clear colored, which I hear doesn't have the same effect and formula after reading the reviews.