You said .30 cal not .22 rifle.
Apples and oranges. I will stand by my thoughts where there is not one single 30 cal rifle that " I'd much rather have a properly loaded .44 than any .30cal rifle."
That may be, as that is your personal preference. But to your general statement on bone, I have taken hogs that have had slugs still stuck in bone. One of my uncles most told stories is bouncing a 44 off the skull of a hog, then the hog treeing him and finishing him off with a 45 from above.
Your statement (to me) implies that FPE hitting the target means nothing, and that is just not accurate. It does mean something, I will go out on a limb and say everything, and you know it with your "properly loaded" comment. Now if you want to argue the amount of energy on target is excessive for the job needed, ok I will buy that argument, I don't agree...to a point, too much energy on target will turn the target into dust with it still but it is an argument that will stand on its own two feet. And you agree that rifles to hit with more energy.
You give it away with the term "properly loaded" I could hit that same animal in your photo with an "improperly loaded" (whatever that is) rifle cartridge and still get the same result.....(and now for the real point)....depending on where I hit it. That is the key, shot placement. We have all read the stories of people killing a bear with a 22 rimfire, your photo means, in your words a hill of beans. You can kill anything with anything. I had been doing a deep dive on the american indian, and in one tribe a right of passage was the killing of a buffalo by yourself, with a bow, a bow made with 300 year old tech....the american indian before the whites came are a stone age people, and still they killed animals that size. So in a way that goes along with your FPE means nothing (not really but I will get to that) as they could take it with a stone age bow......if the shot was in the right place.
What that extra energy does for you is widen your margin for error, and with the slightest error gives you a greater chance to take the animal in an ethical manner. Again to the stories, we all have them about someone (never us) tracking a blood trail for miles trying to find that deer. And I think we can all agree that in cases like that, that was a bad shot. Modern rifles, and even "primitive" rifles (What MO calls it) hit with a ton of force, it is the energy impacted on target that does the deed, if not why did all those hunters in history going after big game that wanted it dead right then and there, think wide destruction of bison in the us. They shot those huge rifles with those huge bullets because it felt manly? Nope, They needed the range, nope, bison are really really stupid, they just stand there not knowing why George over there fell down dead. You just line up on another and bang away, rifle get too hot, pour water on it and keep going. They wanted that energy to drop the animal and not chase it, more easy for the crews skinning them. (on a side note hard to imagine our .gov promoted the destruction of an entire species to "tame" the indian)
Energy is what matters, will agree that the energy in a hand gun is "enough" provided the shot is right. That extra energy is needed for a margin of error.
And I have little doubt the animal in your photo DRT.
Sorry but FPE on target is the thing doing the job. Man I could babble on with examples but this is already too long.