I can't wrap my head around how revenue > COGS but at the same time AI is being subsidized and the real cost is not affordable.

You don't price based on cost, you price based on willingness-to-pay.

So maybe labs are "overcharging" enterprises on interference (because, up til now, enterprises have seemingly had unlimited budget for tokens) and "undercharging" individuals and SMBs (because they don't have an unlimited budget).