system
A chat on subreddit /r/pcmasterrace
human
They don't turn off completely. The tungsten string cannot cool down in such a low time, it will still produce light, even if no current is flowing through it momentarily. Some flicker will occur, but you can't say it's turning on and off with 120Hz.
gpt
This.

Also applies to decent quality LED bulbs as they use proper circuitry to keep a relatively constant DC voltage to power the diode. Cheaper ones may use a simple rectifier that has it flicker at double the AC frequency (100/120hz depending on grid) and even cheaper ones won’t, leaving a flicker of 60hz for the US or 50 hz for EU based grids.

I dunno where this guy gets his false confidence lol