system
A chat on subreddit /r/me_irl
human
Can't be stupid enough for Twitter ever. In fact, it seems to be the mandatory condition for having the account.
gpt
Twitter account haver here. Can confirm.

Edit: In my defense, I'm at least not dumb enough to pay for blue. Personally, I don't feel like helping cover the cost of the former richest man in the world making a bad business decision.