I think it has to be looked at from a couple of perspecives; one, the individual dog owner/individual situation... and two, the over all population, JQ public, rescues, shelters...a sort of umbrella-look at this. If I ever get another male pup, I will wait until he's full grown to neuter or not neuter at all. However, not everyone is conscious of the serious consequences of random breeding and oops litters. Most people are just not thinking about the millions of homeless dogs languishing their lives away in little concrete cells.
So, the weighing of pros and cons comes out a little differently, depending on whose perspective you're viewing. Bone cancer, other health risks associated with early neutering are indeed horrible. However, I think what's infinitely worse is huge numbers of unwanted puppies spending their lives or large portions of their lives in shelters, with no family, no real home. Or puppies popping out by the thousands, only to be euthanized because they have no home and had no choice.
So for the public, the mainstream pet owners who are careless and clueless about the ramifications of letting their intact dogs roam and breed over and over, year after year, early neutering is definitely a pro. imo. Who cares about bone cancer? A handful of dogs dying from bone cancer or millions dying because there are too many of them? Or millions living a miserable life in hell?
For those who are aware and conscientious, responsible about their intact dogs, then holding off till they're full grown is a viable option and probably a pro, not a con. So, I don't think you can say one way is a pro always and the other way is a con always.