Boomer rant about “ Njan mind aan”

Unfortunately I don’t live in coconadu, and the last time I visited home, I met a lot of people (friends and friends of friends) saying “njan mind aan” to agree to a plan. For me, this sounds fking absurd. I agree what you are thinking in your mind bro, you are your thoughts. You don’t have to state that. Just say I am up for it, or, njanind! What else am I missing by not being at home?