It depends on the bullet as to whether the shoulder shot is ethical or not, IMO. A shoulder or shoulders deliberately shot with a C&C bullet proves you have no regard for a big game animal.
A monolithic will do far less meat damage and produce the same immediate drop when shot right through the shoulders...
Not knowing the difference is telling...
It took me 20+ years to recover a 7mm Speer 160g Grand Slam, a quality C&C bullet but C&C nevertheless. They kept going through the deer and elk. (And a few coyotes, prairie dogs and antelope.)
When I did finally recover one it had destroyed both shoulder joints of a 5x5 bull, putting him straight down on the ground.