The Russians I believe built over 10,000 “Stalin organ” rocket launchers in WW2 and used them in “shoot & scoot” mode.
https://militaryhistorynow.com/2021/01/19/stalins-organ-10-things-you-didnt-know-about-russias-katyusha-rocket-2/
all himars is is “shoot & scoot”
they say is high precision but that requires targeting solutions, and set up gets you killed