With better bullets and powder these days and with the 375 cartridges having been known to take hundreds or thousands of elephant back when powder and bullets were not as advanced, why do people say more is needed for elephant? I know I would feel more comfortable with something like a 470 Nitro Express for elephant but it just makes little sense to me why this would be the opinion these days. Is it about more confidence in larger bores?

Well I don't know if you played football but I will us an analogy from there. Yes a 180lb defensive back that runs a 4.5 second 40 can tackle a 280 lb fullback head on. But a 320lb defensive tackle running a 4.7 40 will do it much more smash.

I will take my 500 Jeff over my 375 every day.

But a shooter must be able to shoot the bigger rifles as well as they shoot the 375 and that is where the rubber meets to road. Most folks can shoot a 375 well but the bigger rifles not so much

Slipjig, you answered your own question.

"I know I would be more comfortable with something like a 470 Nitro Express."