> What is the difference between volume and liquidity for the purpose of this discussion?

You're the one asking "Why would liquidity matter here?", you tell me. Like I said, they're correlated well enough that it doesn't really matter as far as I can see.

> This is wildly rare in public markets.

Yes, but it's what happened here.

Option markets are quite often more liquid than the underlying in India which is why Janestreet was able to pull that off.

Retail folks use options to gamble. Apps gamify access/trading. It's really odd like that.