Here are my thoughts, they are certain to ruffle some features.
Here in the states, for deer hunting especially, there is an idea that a standing broadside shot under 200 yards is the only ethical shot to make. That's our culture - but it is not the way it is around the world, and just because it is our culture doesn't mean it is right or absolute. And there are definitely cultures around the world that are critical the way Americans hunt whitetail.
Where you hunt, and what (animal) you hunt, makes a big difference in shot selection. What I learned in Africa is that being a "proper" hunter means that you should be proficient to take many different types of shots, from many different circumstances. It is not uncommon, for example, in Africa to have to make a shot freehand, or perched in a tree, or leaning out over a cliff. It is also not uncommon for the trophy animal you've spent 7 days searching/stalking not to offer you a standing, broadside shot in the heart/lung area.
Whether your PH says it to your face or not, if you are the "typical American deer hunter" that will only wait for the standing broadside at relatively close range - your hunting ability will be criticized. No PH is going to have a good opinion if that trophy Kudu or Nyala only offers you a neck shot through a small opening in the brush and you have to standing with one foot in a hole and the other on a rock - and you pass on the shot. They EXPECT you to make the tough shots.
While where you hunt here in Texas, you may have the luxury of passing on any shot that isn't a "perfect setup" - and that's perfectly OK by the way - it would be wrong to criticize someone who has the comfort, experience, and ability to make a more "challenging" shot.
The flip side is trying a shot that is beyond your comfort zone or ability is never a good idea or ethical. Even in Africa.
For me, I like to think I have a number of shots in my arsenal and have the comfort and confidence to use them when needed. Sure, I would LOVE to have standing broadside shots all the time, but I am not going to pass taking a shot on the target animal if is not "perfect" - provided I have supreme confidence that I will make it and it will drop the animal quickly.
My daughter, for example, is extremely fond of neck shots for some reason. She is very confident and has perfect record of dropping animals with that shot "through the joint". Therefore, on our trip to Africa she didn't hesitate to drop a trophy Nyala with a perfectly place round shooting through a small opening, uphill, and broke the spine at the base of the neck. You can argue "ethics" on that shot all day long, but the fact of the matter was the animal was instantly killed and if she didn't take that shot, it was likely we would have never caught up to the animal again.
In addition, I have been hunting on smaller or irregularly-shaped properties where we caught up to the target animal near a fenceline, cliff, or other boundary that we would have rather not see the animal cross. It was needed to drop the animal RIGHT THERE, as even a short "run off" of 10-30 yards would have not been desirable. Therefore, the "optimal" shot in these cases was a neck or base-of-the-skull shot. No issues.
By the same token, I am not advocating taking these types of shots when they are not needed, or when a pass on the animal is indicted, or just to prove marksmanship. Just because you can, doesn't always mean you should.
In conclusion on this topic, I don't think there are any "absolutes", and therefore any judging of someone should be carefully considered. I believe that every hunter should hone their ability and confidence to the point that if a non-optimal, non-typical shot is warranted, it can be executed with success for an ethical kill.