Continuing my thought:
If I had a nickel for every time I corrected someone on how to run a tube-fed pump action shotgun correctly, I'd be pretty well off. A lot of folks can't wrap their brain around the idea of loading one round at a time, not when they can stuff in 10 plus at once and have to think no more on it.
Another problem: How many folks under 40 do you know running - REALLY running - revolvers and running them well? The rimless cartridge entered the world around 1893 and rimmed has been losing ground ever since.
With the mag-fed autoloader being the primary subject of leftist scrutiny, other mechanisms need to be contemplated.
Where they fell flat on their face was in not doing this as a pump action instead, although that would damage the option of forend accessories considerably.