I sometimes struggle just to loosen the valve lock nut without pliers because sealant has got in there and cemented it stuck. Definitely worth carrying a set IMO, but particularly with tubeless.
Malcolm, to demonstrate the correct technique, can you shoot a video of you repairing a smooth road tyre with one of your worms (no glue) followed by inflating it to 6 or 7 bar and then leaving it to sit for a few minutes? Mine always push their way out no matter how tacky the worm is, and looking at other forums, I am not the only person with this problem.
BTW the Dynaplug kit I bought
was £22.60 with 4 plugs so a good bit shy of £40. Extra plugs are less than £2 each, which is expensive compared to worms, but you can't really argue that they aren't easier to use and much less likely to work loose. I have used one plug since I got them so the cost is insignificant to the other cycling related stuff I buy. I have no confidence in worms, but I'm 100% sure these will stay in.