Never bought that saying for a second. Hell the 30-40 was already in use by 1892. the 30-30 wasn’t offered on any platform until 1895. By 1903 the 30-03 was available and by 06 we had the 30-06. All of these rounds are much more capable than the anemic 30-30 and hunters knew it. While a know a few people that have 30-30’s (Mainly just to have a lever gun in the collection) I know of none who seriously consider it a go to deer caliber. I started hunting in 1957 and have spent many wonderful hours around a campfires since. The merits of the 30-30 as a capable deer rifle were never discussed. Hell in the last 60+ years I’ve only seen 3 actually used for deer hunting. I guess what I’m saying is I call Bull Chit on the old 30-30 claim.
Now with all that said let me say this. Yes the 30-30 has enough gas to be a deer rifle just a very limited one due to power and bullet design. Keep it for what it’s designed for and it actually fares pretty well. It’s about a 50 yard rifle with open sights and a 100 yard rifle scoped, keep it there and your OK.
Now there is one area where the little 30-30 does fairly well here in Texas and that’s hog hunting thick country. Short and quick with open sights and enough gas to take full size hogs, just keep them in it’s favorite range.
You raise some excellent points. HOWEVER - folks tend to forget that our grandfathers did not hunt the way we do, because they did not have the same gear available. Sure, the .30-40 and .30-06 were "available" around the turn of the century, but what commercial firearms chambered those cartridges? The Winchester 1895 comes to mind - Americans were familiar with lever action rifles, and the demand for bolt action hunting rifles apparently didn't start to increase until the 'doughboys' came home from The Great War. And the vast majority of hunters used iron sights; affordable scopes didn't come on the market until after the Second World War/Korea. An awful lot of things changed in the half-century before you started hunting.
Just my two cents worth...
;^)