I don’t think this is true. I lowered my difficulty to easy for the wtc800 and it was al lot, I mean a lot, easier.The AI simply drivers slower.
NOTE: The races on world circuits that have chili peppers are not affected by this. They have their own difficulty that can't be changed.
Take the WTC 600 Championship. Try to win it in easy mode (pi** easy), and then try it on hard mode. You'll see the big difference.
They’re not.are the credits affected in easy mode? could be a handy feature for grinding people who dont want such intense or serious racing.