Wow, there sure are a lot of high horses here. And I thought my horses were tall!
There will always be purebred dog breeders, and there will always be mixed dog breeders (yes, even responsible ones! Can you imagine??
). No purebred dogs are going to go extinct, no need to worry.
I don't even think it would be a bad idea if they did do a mixed breed pedigree just so that people can track their dogs lines and they can be aware of any genetic issues. Mixed breeds deserve to be healthy too.