What does the second post credits scene mean?
Finally, there is the post credits scene, after what seems like an endless list of super-talented computer effects artists that managed to make the preceding film look so nice. We're back in Scott's house in San Francisco and pan over a television that's on the Emergency Broadcast System, so we know we're in a world after the Thanos snap where infrastructure is in chaos (see Infinity War's post credits scene, helicopter crash and all). We move through the house, hearing some rhythmic clicks, until we settle on the giant-sized ant from earlier in the film, still stuck in Scott's routine, playing the electronic drums.
This shot was in the trailers for Ant-Man and the Wasp, and by the time the very end-of-credits comes along, you've probably forgotten that you saw the giant ant doing a lot of things in the movie, but not playing the drums. That was saved for the end… puzzlingly.
Why show the ant here? Assuming they didn't leave the poor thing in a hellish loop of a man's life for no reason, we can infer that the ant is there to play the same roll he did in the main movie's plot: to act as a placeholder while Scott is out Ant-Manning. This would mean only the Pym family, Ghost, and Bill Foster are on the run, and Scott actually does manage to fool the feds that he's abiding by the terms of his parole. Is he doing that by letting that giant ant live his life in his house while he's out? Or is that scene even further into the future, letting on that Scott is out helping the Avengers already, forgetting that he left his ant-double on his loop?
That's some Westworld-level complexity for a post-credits scene. Or it could just be a funny shot of an ant playing the drums. Not everything is Nick Fury pulling out a modified pager from the 1990s.