Older games become interesting to watch, mate in 6-8 puzzles become tenable, chess books about specific openings make more sense. Once a player knows how to finish basic endgames and accord himself properly in the middle game, they have the tools to grasp opening theory. From there on, there is a huge body of information about opening theory, playing styles, control and leverage of center, etc etc.
Much of the ink spilled about this game is a bit impenetrable without some acumen. But with enough appreciation to the past and present trends, one can fine tune one's playing style and really make the game your own.
Not all other games have this feature. If I play Catan with my friends, it's fun, but then the game is over. I'm not going to analyse my game and discover new tactics or strategies, like I will with chess.
Important to remember this is not a universal truth for all people.
> If I play Catan with my friends, it’s fun…
Interestingly, you and I seem to be opposites here. I only play chess for fun and never care if I improve, but spent thousands of hours in my college years analyzing and improving at Catan. I wonder if this is simply a matter of whether one prefers deterministic or stochastic games for optimization.