First of all there is and has been a commercially available 22 WRM double stack semi-automatic pistol around for a long time. It is called the KelTec PMR 30.
https://www.keltecweapons.com/firearm/pistols/pmr30/
“......In 2008, our Chief Design Engineer, Tobias Obermeit had a vision to build a semi-auto .22WMR pistol that holds 30 rounds in a flush-fit magazine. Roughly based on an early, futuristic looking George Kellgren design, the PMR30 was released in 2010 with high praise and stands out as one of the most innovative handguns in the world today.......”
“.....This is a factory Kel-Tec PMR-30 30-round magazine in .22 WMR.....Featuring a double-stack magazine design, it holds up to 30 rounds of ammunition and is made from lightweight, durable polymer. The magazine has a unique shape and design which allows it to fit flush with the pistol grip, making it more ergonomic and comfortable to use. It also features witness holes that allow you to quickly see how many rounds you have left in the magazine......”
And yet we have people complaining that the 5.56x45 is not enough cartridge for the job.
yet the 22mag is such a weak sister to that