It is impossible to be really good at everything.... when I optimized for work, my fitness goals went through the window. When I optimized to get a project done, my reading (books) went down as well. When I optimized for fitness (working out and soccer), my work and side projects started progressing slower. It is very hard to work on your project at home, when you are in a intense bulking, or 'cutting' phase, and onc…
I have a "rule of 3". You can be quite good at 3 things (give or take). One of them will probably be your job. One will probably be your relationships. You have time for 1 more. If you keep changing your mind about what that last one will be, then you will only be good at 2 things. There are ways to be good at only 1 thing as well.... or even 0...
For example, it's only been fairly recent since I dared to claim I'm pretty good at programming. And not even all aspects of it, but there are some aspects where I really notice I'm better at it than my co-workers. I've been doing this professionally for 20 years, so I guess it's about time I got good at it.
I've always thought I was pretty good at sailing; I think I have a talent for it. Used to do it a lot back in the day, but haven't been able to sail much in recent years. I'm not doing the upkeep, but I don't think I forgot any of it. I think I can jump in a boat and sail safely while teaching someone else. I don't think sailing costs nearly as much upkeep as something like physical fitness, which drops pretty quickly once you stop exercising.
I'm good at cycling, but doing the upkeep for this is easy: just take the bike when you go anywhere. I'm not as fast as when I was younger, but still faster than most.
I've been playing RPGs all my life, but I think I only recently got good at GMing (I've done it plenty of times before, but it was very hit and miss, and the misses sucked bad). But that's something I've been putting a lot of time and effort in lately. I clearly don't have any natural talent for it, but I've managed to accumulate quite a bit of experience over the decades. I still lack the discipline to do thorough prep, but experience fills in a lot of the details.
Despite having played a ton of different instruments (drums, keyboard, guitar), I've never gotten good at music. I lacked the discipline to practice every day, and though I would like to be better at it, I'm clearly not as passionate about it as I am about gaming.