Apparently fourth-generation LED tube lights are designed not to flicker.
I googled for G4 LED tube PWM and got products that say they are G4 LED tubes that use PWM.
Pretty sure 100% of LED products sold anywhere use PWM if you don't use them at full brightness. I sometimes walk around lightning stores with a slo mo camera and see PWM in every price bracket.
Actually that's not true, my first thought was "just use a layer of phosphor excited by the LEDs", but fluorescent tubes do that and people used to make the same complaints about flicker, so.
Looks like "flicker index" is a useful(?) search term, anyway.