The geometry of a cutting edge is determined by the function of the instrument.
A convex edge is designed for abuse in repeated cutting, and simplified sharpening. A knife, like the one you dress your deer with, is going to be in use during the field dressing, skinning and quartering of the deer for maybe an hour's worth of cutting.
It needs to have the edge to stand up to the abuse.
Then, you're not going to throw it away, so it needs to be easily re-sharpened.
The broad head you shot the deer with, on the other hand, only gets used ONCE on the same deer.
It needs to slice very cleanly and travel into the target as far as possible severing arteries along the way.
You're not going to shoot that deer 20 times with the same broad head..
The edge only needs to last 1/2 second.
You may sharpen it, you may not.
They're relatively inexpensive in relation to your knife.
When they get dull or beat up most of us just replace them.
Sort of like your disposable razor.
Sharp, flat grind for broad heads.
Convex for knives.