Why do the corvette c7 tail lights flicker??

If you're asking why they flicker in video replays, I think they're LED lights. LED lights flicker/pulse at a rate that is usually imperceptible to the naked eye but they do pulse and a video camera will usually be able to catch them refreshing similar to how a TV can be caught obviously refreshing on a video even though many people don't really notice the refresh rate with the naked eye. I believe that essentially the refresh period on the video recording device is out of sync with the refresh period of the light/TV or whatever looks like it's "blinking" upon playback and that's why it appears to blink on the video.

If you're noticing them flicker in person with the naked eye, then maybe you're just more sensitive than the average person is to pulsing lights? A small portion of the population does tend to notice the refresh rate of slower refreshing (60Hz) monitors for example. I know that old CRT monitors set to a refresh rate of 60Hz used to drive me nuts because they always appeared to flicker to me. I do notice the tail lights on some newer Cadillacs flickering as they drive past but I've not noticed it on a C7 Corvette before. Honestly though, I don't see many C7s around where I live. Next time I do I'm going to look for the brake lights pulsing though because you've made me curious.

You may have a bad alternator that's leaking AC ripple into the electrical system. Better get it tested right away so you don't end up frying a control module or the PCM.

LEDs can flicker at unsteady voltage

Loose wire.

Idk