I agree with you, in principal, but I have found there are two schools of thought when it comes to making a clean kill on a deer. The old-school guys will tell you that a medium-bore round at moderate velocity will expand well, leave a great exit wound and not result in a whole quarter of meat being bloodshot. The high-velocity crowd will claim a small, pointed bullet going nearly twice as fast as the old round-nosed stuff will cause a ton of "shock" when it hits, resulting in spectacular kills! The interesting thing is, they're both right, and both claims are absolutely true.
The .243/6MM Remington class of cartridges is hotly debated and many people will claim that they can't be relied on to kill really big deer. Hogwash. If a hot 24 fails to kill ANY deer, at less than 400 yards, it was because the shot was not placed where it's supposed to be. In the majority of those instances, a 338RM probably wouldn't have performed any better.
Like I said, killing a deer, whether it's white-tailed, mule-eared, tiny or huge, north or south, is simply not that hard to do. Deer are fragile critters and if you can hit that imaginary basketball between, and slightly behind, their shoulder with anything from a .243Winny up to a 45-70, the thing just ain't gonna go very far.
Now, if you are sometimes compelled to take shots at deer that are facing straight at you, straight away, or steeply quartering, larger caliber bullets will have more power to push through that extra bone and muscle to reach the critical heart/lung area. I've taken those shots, when that was all I felt I was likely to get, and I will probably do so again, in the future. That's why my favorite deer gun is a .270, even though I'm not allowed to hunt deer with it in this dumb state of Indiana.
However, my dad has shot a .243 for his deer hunting ever since I can remember...at least 30 years. Of the very few deer that did not die immediately after being shot with that gun, the dramatic demise of all the others strongly suggests that the failure was not one caused by the cartridge, but by the hunter. I'm sure we can all understand that.