Use headsets with leather caps, it should isolate most of the noise out.
This. The leather really makes a difference. My Steelseries 7Xs came with cloth caps that I didn’t like. Ordered their leather ones and they’re way comfier and seal better to block out more outside noise. Still a little soft and loose fitting, so I’ve ordered the Wicked Cushions leather caps everyone seems to rave about and hoping I like those even more.
Cranking surround sound isn’t an option for me as sound carries too much in our old house and I’m usually gaming while my wife is either working in the next room, watching TV in the living room also beside my game room or sleeping in our bedroom upstairs above it. Hell, cranking it loud enough to drown out traffic etc. would probably bother the neighbor too since our houses are like 10 feet apart and there’s a window in my gaming room that far form a window on her living room.
Headphones are just a must for gaming at a reasonable volume in a shared space and in a city with ambient noise to block it. I don’t have to turn the volume up all that loud with leather caps to block out the traffic etc. Plus my surround set up is old and cheap anyway so I honestly get a better experience with the 7xs (and Sony Golds last gen when I didn’t need something that also worked wirelessly on Xbox). Wish I’d just ditched the surround set up for a sound bar (just for TV/sports watching) when we moved as that would be less wire and speaker clutter and the surround rarely gets used anymore.