I find these comments unhelpful. If the question was, "I ride exclusively on the interstate, speed 20 over the limit, and I like to watch videos while driving, how can I get rid of the dinging," then, yes, the answer should be, "Wear your seatbelt."
But there are many instances where the annoyances of a seatbelt outweigh the benefits. For example, driving through empty fields with lots of gates, launching a boat, backing up to a trailer, etc., do not require a seatbelt and the dinging can be more than annoying.
If you don't want to help, then fine. But adding snarky remarks like, "Just wear your seatbelt," is not helping and just trying to start something.