MagiStream

Vet assistant/tech here (not sure what's the correct term since English isn't my native language).
Though I don't have much experience in the field yet I thought I'd share my thoughts here.

First of all I don't think muzzles are necessarily bad as long as they have room to breathe and pant, though they should only be used in public spaces. At least here in my country (Spain) those dogs who are considered from "potentially dangerous" breeds are legally obligated to wear them. (This is a very controversial topic best left for another time though)

We also use muzzles in clinics in some cases of nervous dogs, it seems to soothe them and also prevent bites. Especially since when a dog is hurt it can lash out without really realising.

As for the pronged collar, I'd say there are better alternatives if you have a rebellious/big dog. A good example is this harnesss/collar that also wraps around the muzzle so the dog can't pull without its head being moved sideways (it doesn't harm them at all).

Having an animal "behave" through intimidation/threats/being harmed is never a thing I will accept, and same goes for some "training" methods I've seen that involve stressing a dog. Positive training may seem more complicated but its much better in the long run.

I don't have much knowledge on pronged collars, so I won't speak on that topic. But as someone who's owned a greyhound in the past, muzzles were very important. Recently, I was trying to adopt another greyhound and many greyhound-specific shelters required or highly advised the use of muzzles. They have very thin skin and it's easy for them to huge tears by accident when playing and running extremely fast. Specifically, greyhounds playing together should be muzzled. As long as the muzzle is properly fitted (i.e. allows room for the dog to pant), then it is perfectly fine and ethical to use.