More deer have be taken with a 30/30 then all others combined.
Do you need a magnum for deer? No.
Here, we can legally use a soft point .223. Bullet placement is critical.
If you hand load the 30/06 is perfect. Heavy bullet, heavy charge for elk. Reduced charge and bullet for deer. Or use heavy charge and bullet for deer. Dead is dead. You get the idea.
Don't be duped by the gun writers. Don't be fooled by sayings suchs as
"carry the largest gun you can comfortably shoot".
It has been, and always will be about bullet placement.