I gather the (reputable) breeders are now getting rid of the low-slouch
A it didn't look right
B it caused heaps of grief for the poor dog - relating to hip etc issues
The great thing that I have seen recently is that many breeders are now advertising "straight backs" and are so gradually breeding out the horrendous deformity
The Kennel Club in the UK has an awful lot to answer for; their "characteristics" of breeds in many cases are no more than deformities