GGs is shorthand for good game or good games, a phrase players have typed and said at the end of competitive matches for decades across shooters, fighting games and sports titles. Saying it out loud, as in this clip, became common in voice chat and streams as a sign of respect regardless of the result. The man GGS version spread as a soundboard reaction because it captures that exact end of match courtesy in a few seconds, making it easy to reuse whenever a game wraps up online.