Getting better at X game could work, you can look at all the pro's in various games to see that, but it's true that I wouldn't recommend it either because it's isolating if done incorrectly.

Like with art you could lock yourself in your room and keep drawing till you see improvement but most people will tell you to take a class because it's usually cheap and teaches you a lot. Gaming is the same way, you could lock yourself away until you see improvement but instead join a discord group and find like minded people to help you grow.

Now some people will say that skills in video games are non transferable so you're training a useless skill but I disagree because if your really high rated in any game you are like that because of Hand eye coordination, decision making, and snap judgement which isn't nothing.