Honestly it’s getting to be too long ago to compare to modern teams. Lots of rule changes. All the competition has optimized nutrition and strength training. Unlike back then where there was just a handful of teams that even looked like the same species as us.
What I will say is if Indiana completes the 16-0 season it will be a lot more impressive than any of our natty runs. There is really no shame in that. It would probably be the most impressive single season ever given their history.