When I started hunting in the late 40s, the 30/30 was far and away the most popular deer cartridge in America.
Others like the 300 savage and 35 rem were very popular also. In fact they were no doubt the 3 most popular
cartridges in states like PA which had lots of deer hunters. My first gun was a 94 Winchester in 30/30 and my father
and brother had one also. We all soon moved to other guns and cartridges with me going to a pump 35 rem and they
each to 99 savages in 300 sav. The 35 was a better choice but other than bullet weight not by much in my opinion.
Neither of them are what id today call a good choice of cartridge for deer hunting.
But having owned and killed deer with both, id opt for the 35 rem over the 30/30.