Never self-pour, but there were times you could request wine in one of the TG lounges - maybe the D concourse one?
BR and old SQ lounges were self-pour.
Wine has been available in the main D lounge. This area was located immediately to the right after descending the escalator following the dedicated immigration process.
I can easily imagine most pax moving in the opposite direction to the ‘desk’ area to collect a wifi chit, and then moving to the areas where most pax were congregated. Unless they asked staff, they’d never find the wine.