There are communities devoted to deep understanding of games. These tend to be in the Speedrun or Tool-Assisted-Speedrun communities. Both tend to be high time investments, but can reveal deep understandings of a game, including how to exploit coding flaws.

Of course, gaming is not the only hobby that a person can gain satisfaction from, and you can similarly get that sense of growth from other goal or skill based hobbies. Painting, music, or even just learning a foreign language. The payoff may be much greater than mastering a game, as society at large tends to value these "worldly" skills more than gaming skill.