Terminal Velocity is not the only big difference. Your also talking about a huge difference in sheer energy (PSI) especially at extended ranges. The number one big difference between a .338 and a .375 is about 1000 yds. and (ME) especially beyond 2,000 yds.
This has been argued over and over again all over the place and it's still argued even know the facts are in the math. Read and find out on your own but the .375 is putting to shame anything in it's class to include the .408 and .416 which are proven better than the .50 cal. Most people would not put the .338 in the same class with the .416 and .408 so why put it in a class that is proving time and time again how much better it performs.
Look deeper if your not a believer
Just my 2
¢ worth.
Cheers,
-RiP