That does depend on which wifi standard. Wifi 5 is only 5ghz, wifi 6E is only 6ghz, and there is no wifi 6 on 6ghz. 6 being separate from 6E.

Check out the table on wikipedia: https://en.wikipedia.org/wiki/Template:Wi-Fi_generations

Yeah, I've been playing around with the "new-ish" ESP32-C6 chip. It's a $6 dev board, so probably in the sub dollar range in bulk for the chip itself, and has WiFi 6! I originally thought WiFi 6 meant 6ghz, but it's limited to 2.4ghz.