Not to be argumentative here, but we are talking in terms of thousands of inches in the bore and probably an 8th of an inch when it comes to shot stacks. I see the argument because I have used this to pontificate why I love to shoot 16ga in the uplands...but I admit, I see no difference in how dead pheasants are when shot with a 3" 20ga.
In my opinion (and that's all it is) a 10ga is romantic albeit effective gun for heavy duty waterfowl. The guns are heavy, the shells are expensive, and it's only got one application. A 12 ga 3.5" is far more versatile. You can use it for everything pretty much even though it is a jack of all trades I admit. My Extrema in the hands of a skilled shooter with waterfowl experience, I wager will be indistinguishable to a guy next to it with a 10ga.
LOL
Ya OK
No opinion . Here is what I know from a test I did years ago
Own two browning golds 10ga and two golds 12 ga 3 1/2 since new and still have them ( plus 6 or more other 3 1/2 12ga's)
Years ago fitted both with briley choke tubes IM mainly is my pick and the same rsi reloads as far as payload goes and did up 6 or eight different combos
The pattern differences over 50 yards and beyond on paper were night and day especially the duplex loads which I like
The guys I hunted with were all dam good trap and skeet shooters one runs the 100's still and they see a difference when there is the old 10ga in the blind for sure
I remember back in 1984 heading to pei with my 12ga 1100 goose hunting and was in my prime in those years as far as target shooting and joined the two outfitters one day in a blind both were retired RCMP officers and unknown to me using remington sp-10 ga's. Some will know the outfitters I am talking about
About 1/2 way though the morning I seen enough that I said the next year I am going to have one of those and I did and never looked back. A trip to quebec duck hunting over open water with very long pass shooting they actually recommended the 10ga I recall
Don't wager that extrema in from on me in the blind unless you want to lose it
If one only has one shotgun yes get a 3 1/2 12ga but if you do a lot of goose or coyote hunting and can afford another get a 10ga and don't get me started about 16ga since I have a nice collection of those also and love shooting the 16ga so I don't want to start beating on the 20ga 3"

But upland and goose hunting is night and day to me with respect to guns used
Cheers