Not sure what is the debate when it comes to your own dogs. Some owners like to show others do not. Of course showing doesn't make a good owner or well rounded dog, success in show ring isn't the only reason to breed. What you're missing is that many breeders which show dogs also do health test, breed for temperament and other traits. Though not all are good breeders or breed for anything other then wins, it's like anything else there are good and bad show breeders.
You don't have to show to be a good breeder, but lots of people who show Carr about their dogs and are good breeders. Really I don't see a debate in this, it's common dog sense that success in show ring doesn't equal well rounded dog. A good breeders assessment doesn't end with show wins, a lot more goes into breeding.

I would debate early dessexing,which is unnecessary and can be detrimental to the dog,

I love Pembroke Corgis but my preferred type is the old fashioned one from 60+ years ago when they were more agile, longer legged, shorter backed and had foxy heads.

That type of dog would get laughed out of the ring nowadays even though it is nearer in type to the real working Corgis that existed. The same could be said of numerous breeds.

I won't neuter my male dogs unless there is a medical problem or they display testosterone fueled behaviour that can't be worked through.

Personally I do agree with your sentiments regarding the dog show world. My working line male GSD has been used at stud twice (and I hope to have a pup from him later this year - fingers crossed) and he has never been in a show ring. Firstly, it would be a waste of my time and money as he does not conform to what show judges would consider to be a good example of the breed. You may know that there are many different types of GSD and the working lines are like a different breed altogether. He has had the required health tests, has a wonderful temperament and has proven himself to have the drives for work.

It is the same story with my husband's dogs. They are all working border collies (some registered with the International Sheep Dog Society) and some unregistered. They work daily on a hill farm, working over 2500 sheep. Taking them to a show to be assessed would not be something we would consider important in any way whatsoever.