There is alot more to bullets than BC. Given equal on-game performance I'll agree with your statement ; therein lies the rub. I've shot more than a few animals at distances measured in feet. Two elk just last year; one at 50 yards, one at 30 feet. I'd suggest running the ballistics of Nosler partitions against the high BC bullets. There is practically no difference until you get beyond 500 yards.
Regardless of what people seem to think bullets start dropping like rocks after about 400-450. Then there is that pesky little thing called wind. Slipperier bullets fight the wind better - but whats that gain you 2-3-4-5 extra inches beyond 500 yards? When your bullet is already blown off track 6-10 inches the fact remains you still need to compensate for the wind. If you can lob your bullet into the target correcting for 6-10 inches of wind drift, you certainly should be able to correct for 8-15 inches.
Which brings me to the reason why I'm not a fan of shooting beyond 500 yards - how many animals are wounded and lost because someone mis-read the wind. To hear it told on the Fire, there isn't any. Which is BS.
I respect the opinions of others that see it different but I know what works for me and my style of bunting. I'll stick with bullets that perform up close and as far as I'm comfortable with shooting. Seems to have worked for 40 years give or take.
