I am not sure people realize how centralized is the development of Knots. There is very little if any code review and a single person with write privileges to the repository.
I guess he can sneak a malicious code any moment without people noticing. He or somebody else if his account gets compromised. And his accounts were compromised in the past, when his Bitcoins were stolen.
I hope the above poll is not representative and 30% of the network will not run Knots just for this reason alone. Nothing against Luke and I am no taking sides in the OP_RETURN debate.