Speaking of musicians, I wish I had learned to play music. Every place I've worked there have been some very talented musicians working there and I wish I had the skills to play with them.
I currently keep an electric guitar in my office and picking it up and playing (unamplified) is a great way to break my concentration when I'm stuck on a problem. I still can't really play though...
Don't "noodle around" as a beginner, because practice makes permanent and good form is everything.
Do you want to be actually good and not just okay? Take weekly lessons, follow online tutorials carefully, and practice at least 30-45 minutes 6 days a week, giving it an absolute laser-like focus. (More practice is always better, and preferably in singular sessions, but that's the minimum and it's enough to make progress.) Focus on fundamentals, fundamentals, fundamentals. Treat good form like religious gospel and don't deviate from it, even if it's easier that way.
And since you already have played for a while, you're going to have to spend the first few months of practice painstaking unlearning the bad habits you've undoubtedly collected, which is not enjoyable because it will feel like you're moving backwards.
Do that for a year and people will compliment you on how much better you've gotten. After 3 years you'll be good enough for any semi-decent cover band in town. In 5-10 you'll be better than 95-99% of people who own a guitar and know how to make sounds on it.
tl;dr: it's totally possible to be good at an instrument, but it takes discipline and you have to be very intentional about it.
I'm decent at switching between the basic open chord shapes, can barre some of those shapes fairly consistently, know power chords on the low E and A strings, and know a couple of scales fairly well (pentatonic and major).
An enormous problem for me is a total lack of any sense of rhythm and a poor ear for tone. For example, I've learned a lot of Nirvana's About a Girl and if I try to play along with the CD I'm okay until the vocals start. At that point I start strumming the rhythm of the lyrics rather than following the beat. If I focus on my rhythm, then I start messing my chord changes and as soon as I focus on the chords, I lose the rhythm. A lot of my practice is with a metronome and I think I've developed a dependence on the click.
The only song I've learned from start to finish in over 20 years of playing (other than toy songs in exercise books) is a simple version of Dylan's Knocking at Heaven's Door. Oh - and I know 90% of The Breeder's version of Drivin' on Nine.
The lessons were a mixed bag. The Suzuki school was the worst because they made sure there was no fun to be had. The best was probably my first teacher that I met through a night school community college learn-to-play-guitar course I took in 1996.
In that time I've become a father and my kids have taken music lessons. Watching how quickly they learned their instruments and seeing how great their hearing is (one kid has perfect pitch the other has very good relative pitch) really makes it clear how poorly I've done with this.
Now I'm 33. Some guy on reddit said he'd coach me online, so I gave it a try. I'm tracking my macros and doing the workouts he recommends in my own gym, and the progress I'm suddenly making is kind of freaking me out. In a two week span, my legs have gotten weirdly big. My upper body looks lumpy. Every session I can lift more weight, and I'm getting stretch marks on my chest and back, simultaneously losing the relatively small amount of fat that I have and gaining muscle. I'm on the fast track to Gainsville, and all it took were a few relatively minor changes.
In retrospect, my problems were I wasn't tracking my calories or doing enough volume, and now that I have a trainer that put me on the right course I'm making a ton of progress.
My point in telling you this is maybe you just need to find the right teacher and practice regimen to make progress, and if you find it, you'd be surprised how fast you get good.
As an adult, maybe it will take you twice as much practice to get good than someone who's, say, 13. But you can still get there, and it's still worth it.
Perhaps you simply need to try again with a different approach and a different teacher and it will "click." They will give you exercises that will actually develop your ear and sense of rhythm. But you do have to commit to focused practice, no interruptions, and not in front of a computer, nearly every day for several months.
Also, I saw the latter song in some venue in San Francisco in 2008. It was sublime.
I almost got a chance to interview Kim Deal for my college radio show before the concert, but they backed out.
