I played a little as a child (enough to beat my dad, who was a complete beginner). I've become quite addicted in the last couple of years (and yes, I'm 40 now). While I agree with the sentiments that "it's a total waste of time and I should learn something useful", it's still fun to have a challenging distraction.
One thing I've found it quite good for is _learning to lose_. I _hate_ losing at games, even now, but, the nice thing about being a beginner chess player is that there are bazillions of people better than you to play against, and lose to!.
On the topic of improving, as others have said, the training puzzles on lichess are great. I've also got quite a lot of value out of [0] chessable.com . Nice little site, teaches you some basic openings which are really fun when people fall into the traps!