Hello, I'm Dr. Deb and will do my best to help you today.
First, congratulations on the newest member of the family:) Golden puppies are certainly some of the cutest out there.
As to your concern about the kinked tail, I've done a fair amount of breeding and have many breeders who are close friends. When a pup has developed a kinked tail, we always consider trauma even though we may not have witnessed the event.
But, having said that, kinked tails can be an inherited trait and can be passed on to offspring, unfortunately.
As to whether or not it's wise to breed him? When this pup is grown and if he has health and type traits impossible to find elsewhere in this popular breed, so that the potential for reproducing this kink is a risk you are willing to take, then you'll want to disclose this fact to any breeder you deal with as well as puppy buyers who might plan to breed.
Pet people are unlikely to care but those potential buyers intending to show their dogs or to breed may be unwilling to take that chance in a puppy.
It's not been my experience that it reflects other inherited or inherent health issues, though.
I hope this helps.