By the 1940s you would get conflicting results. Still, I think the answer is yes, for beginner hunters right though the 1970s. The .30-30 lever action (generally winchesters and marlins) were pretty inexpensive to buy, easy to get ammo for, easy to use and they were the general rifle of choice to get for young hunters. More than half of the hunters, relatives and friends, that I knew as a teenager were given one as a first hunting rifle. There were a scattering of enfields, Remmingtons, etc. in various calibers from .243 to .30-06, but the lever guns in .30-30 were, by far, the most popular.
But does that make the .30-30s the best? Probably not; but maybe.
As one of those kids with a '94 I never failed to get the game I was after for the many years I used that rifle. Over the intervening 45 years since, I've hunted with everything from .222 to .300 win mag. Each had some advantage over the old .30-30, but I don't consider any of them superior to it. Within it's performance envelope, that gun gets the job done on deer, elk, black bear and more than a few larger varmints. It is a hard hitting round that is plenty accurate out to around 200 yards.
So yeah, maybe it was the best; or maybe not.