I don't think anyone is actually badmouthing the 41 maggie, those who have used it very much knows very well that it doesn't take a back seat to some of the bigger calibers, that is with correct bullets, 250-265 gr, etc. Some don't have any experience with a 41 yet they down play what it can do.
I've used it a great deal on big game & although I know in my head that a bigger caliber should work better I've never actually seen it work that way in the field. I've taken a couple of cow elk that were extremely large & my friends bull moose would certainly be bigger than a large bull elk.
While its never a disadvantage to use a bigger caliber it can work against the shooter if he over guns himself & starts to lose accuracy. Heavy bullets don't need maximum velocity to work, the large mass gets the job done if the shooter makes correct hits & that will never change.
Back in the days before most of us had access to chronographs I thought my loads were going faster than they actually were. Along the way what I discovered was, my loads at 1100-1200 fps were passing through everything I shot, deer, elk, bears, antelope, lion, moose & African game & everything in between. So a little light came on in my head, if 1100-1200 fps is working & my 41 maggies are killing everything in sight.......why do I need more horsepower, answer is, I don't, what I need is accuracy every time, without fail. Give me any angle & I'll hit the vitals. Will a 250 gr 44 slug out perform a 250 gr 41 slug, of course not. We can discuss "marginal" but .019" probably fits that discription quite well.

Dick