the SB12 is the lowest(not counting a B&W "sub") output sub ever tested on Data-Bass, so having measurements available doesn't really help its case all that much imo.
To add some perspective and common sense, by my eyeballs the median subwoofer with test results on Data-Bass has an
18" driver (!) in a 6.2 cubic foot (!!) closed cabinet powered by an
eighteen thousand Watt (!!!) amplifier. For most enthusiasts, meeting one of those three conditions on its own is impracticable, never mind all three simultaneously.
So you are not wrong that the SB12 is one of the lowest output subwoofers ever tested on Data-Bass. The Data-Bass site is very impressively put together. You can even sort the measured devices by cabinet volume.
B&W and SVS subwoofers are the smallest closed boxes. Klipsch is a nice example of a compact passive radiator subwoofer: strong motor for high upper bass output supplemented with resonant output down to 25Hz.
Of the sealed subs, SVS mostly outperforms the larger Emotiva unit as well as B&W.
To me the most impressive unit is JL Audio E110, which outperforms several larger subwoofers with bigger drivers from top to bottom.
what appears to be a higher quality 10" driver from JBL
What makes you assume JBL's 10" driver is better than a time-tested 12" Peerless woofer that has seen wide adoption in home and studio subwoofers?
Now if primary use were for movies, I wouldn't recommend either unless a very small sub were absolutely required.
Four of the SVS subs placed around most rooms will provide more headroom than most people will use. Furthermore, there are movies beyond war movies and the comic book universe.