As it says on that site,
The Golden Retriever findings can’t be generalized to other breeds, or
dogs in general.
Each dog breed has its own set of health risks, so I wouldn't try to extrapolate to cats. Second, that site only suggests delaying the age at which Golden Retrievers are neutered/spayed. I don't think they're suggesting that the dogs be mated once first, just that neutering/spaying should be delayed. Furthermore, this is just one study. The site mentions a "growing body of evidence", but doesn't reference any other studies.
Even if it is true that early spaying/neutering involves some health risks, you need to balance that against the health risks of pregnancy, or being hit by a car because they stray too far from home to answer a "booty call", or injured in a fight between toms. Maybe you'll keep your cats indoors to prevent pregnancy, but they only need to escape once! Plus, I seem to recall there are some health risks associated with a female cat going into heat several times without being serviced. And don't overlook the practical side of things -- do you want to live with a yowling cat for days on end, or the urine sprayed everywhere?
Finally, I adore cats, but the last thing the world needs is more of them. Even if you find good homes for all of the kittens that your cats might produce, that just means fewer homes for all of the other unwanted cats.
If you are still concerned about this, ask your vet's advice about the best age to neuter/spay.
EDIT: More info, from the ASPCA
Spaying helps prevent uterine infections and breast cancer, which is
fatal in about 50 percent of dogs and 90 percent of cats. Spaying your
pet before her first heat offers the best protection from these
diseases.
Neutering provides major health benefits for your male. Besides
preventing unwanted litters, neutering your male companion prevents
testicular cancer, if done before six months of age.
The RSPCA has similar advice.