Is it really true "The shelters are filled with wonderful dogs"?
In my area, the shelters are filled with pit bulls and cane corso dogs. The shelters call them "terrier mixes". The shelters - in my area - are not really filled with wonderful dogs. Those that aren't pit bulls or fighting dogs go very fast with too many people looking for a "wonderful" non pit bull dog.
As for backyard breeders abounding and practicing inbreeding.... really? Sure, when I was growing up, there were "backyard breeders", if you mean that there were more people who bred their pet dog. I don't think they practiced inbreeding any more than the breeders who excessively line breed.
Most of the people who are backyard breeding today are pit bull owners. When I was a kid, in the neighborhoods you would see irish setters, rough collies, old english sheepdogs, all kinds of breeds that now seem to have disappeared in favor of pitbulls. Plus the mix a poos/malts/yorks - but they can hardly be inbred, given they are all - at charitable best - cross bred dogs.
When there were what I considered true "backyard" breeders, they were family pets who at least had *that* temperament test going for them. And an important one it was, however popularly discounted now.
Now it seems the greatest number of dogs available are pit bulls that were bred for the worst reasons and end up in shelters as "wonderful dogs" that need saving, puppy mill dogs (who are often inbred when they aren't mix a malts) and dogs from "good" breeders, who often pursue breeding a higher performance working line dog (GSDS, dobermans, etc) that the average family with kids where both parents work can't give enough exercise or training to handle.
Now it is socially unacceptable - and most people couldn't handle anyway - breeding a dog. But it seems to me that what we have instead are dogs that aren't primarily bred or selected to be family pets. Yes, I know working line dogs can be great family pets, but I see plenty of working line dogs who just have way too much energy and drive to have been placed in the families they are in. The alternative is often dogs that are less suited to family life than the old neighborhood backyard breeders. Now what is in these homes are pits, working line dogs, or puppy mill dogs. In trying to solve the dog overpopulation problem, it seems to me another has been created.
I think too much crating also is an issue. A crate today is often, to me, what a fenced back yard used to be, or a chain, - a place to neglect a dog. When I hear about how dogs who spend a working day and a night crated love their crate, I think about abductees who spend years in a closet or box and forever after, end up sleeping in a closet because its the only place they know and can feel safe. Dogs can love a crate because it is a quiet oasis in a busy household. But if they love a crate because they have been crated day and night and spend 16 hours of 24 in the crate, then I can see how they can be a bit crazy.
A dog doesn't learn much in a crate. In the past, where often the mother was home all day with the pup, and kids were around (more kids too), dogs were more socialized to people. They were also less highly bred from working lines (and less bred from fighting dogs like pit bulls) and thus less high strung. I'm not saying anything against working line dogs, except that they are - rightly - bred to work, and that may be too much dog for the average 2 working parent family today who, when the parents aren't working, shuttle their kids from activity to activity.
Re the woman who was killed by her two dogs, they were pit bulls, so bred to fight, and probably had a pack mentality so if one started, the other would go along. And she obviously hadn't trained them. Would she have been better with two "backyard bred" setters or collies, even if they were similarly untrained? I have to say I think so.
But the pack mentality in dogs can be scary. On a personal note, my neighbor has five dogs, most of them GSDs. They seem to be outside all the time and the owners don't seem to spend much time with them. This is an owner BTW, who got her dogs from "good" breeders, where she was on a waiting list for some time. Three of her dogs got loose and ended up in my yard, across the stream from me and started after me. I was probably 150 feet from my house and I truly feared for my life with three large dogs stalking me. I backed up very slowly and made it in the door, probably because there was a bank down and up from the stream that provided a "barrier" to them. When I called the owner to get her to reclaim her dogs, and said the dogs had stalked me, growling and snarling, she found it hard to believe because these were her "good" dogs - she had some she knew were aggressive but not these. Yet they were fence aggressive, barking and lunging at anything across from their fences. When they found themselves over the fence, they had the same temperament. Any dog in a pack is more dangerous. But also, what dogs are in those packs and homes, how they were bred and trained, and how suited they are, by breeding and training, to be in those homes, is also, to me, pertinent.