That's not an exhaustive list. But between those and 1911/2011 things, I don't
need any other brands.
As for "why," it's pretty easy: Polymer frames are cheaper to make in vast quantities, and, as discussed above, many customers like the lightness of polymer frames... without ever having connected the dots that a lighter frame = more recoil. Get into the games where shooting performance is measured objectively, and you start to see a much greater percentage of steel frames. Most people don't measure their shooting performance, so they have no idea what they are missing.
The difference isn't huge at minor PF levels, but you get to major PF - i.e., most .40 ammo - and it becomes more noticeable. When high-level competitive shooters use plastic-framed guns in divisions that reward shooting 40/major ammo, they often attach big weights to the frames to make the gun weigh as much as a steel frame would:
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