That is top tier Bubba-talk.
Shit does happen, and a poor shot is a poor shot...
Exit wound, or lack thereof has far more to do with bullet choice and impact velocity than caliber. Never seen a "tiny" anything on an animal after being hit with a 143 grain ELDX. In fact, wound channels are typically on par with those I've seen courtesy of 300WMs. Heck, the baseball sized exits they leave would be right up your alley!
A 6.5 (and smaller) projectile is every bit as capable, and I'll even go so far as to say MORE capable than heavier/larger calibers... because it's easier to put the bullet where it needs to go...so why handicap that efficacy with bullets that cause narrow wound channels just because you want a guaranteed exit?
Put one in the guts with your mono bullet and your day is likely going to be more shitty than the guy who stings one in the wrong spot with a more frangible bullet.
All of this has been covered ad nauseum, and it continues to be brought up with completely unfounded statements like yours on exit wounds.
Take 10 minutes on YouTube and watch what a monolithic bullet does in gel, and what a Berger does...then ask yourself which one is more likely to exit, and which one is more likely to immediately incapacitate an animal.
I'll be carrying my .243 most of the fall in Montana, will report back on how many exit holes a 90 grain ELDX pokes and how many deer and elk are dead