I have always been curious about this. You will rather frequently see a thread from someone just beginning to play an instrument in which they ask the question "How long does it take to get good". The post is often met with multiple replies that all basically boil down to some version of "it depends". We all know that "it depends" is the correct answer, but I am not sure it is usually very helpful. With all that being said I would like to ask the question in a different way. How long did it take you to get good? How long was it from when you first started playing an instrument until you were regularly playing with others? How long until you joined your first band or music group? How long until you played your first gig? How long until you felt like you were competent or at least felt comfortable referring to yourself as a bass player or (insert instrument) player, or musician?
To get things started I have been playing bass for a little over 3 years. I joined my first band about 4 months after I started playing. It was a rock originals/cover band that was apparently very desperate for a bass player. Three bands later I played my first real gig one year and three months after I started playing. After two years I began to feel comfortable referring to myself as a bass player and musician. I still do not feel like I am very good, but I get better every day.
My experience really has no relevance to anyone else's. We all have different levels of talent and we all have different access levels to people willing to play with us.
I started banging on piano and fiddling with viola and guitar when I was a little kid. My formal music training started in 5th grade orchestra class. I played viola because we owned one and I thought that was cool. For some reason I really wanted to play bass though and pestered my orchestra teachers for several years until that become a reality. Within a few weeks I was the first chair bass player. The other bass player had been playing for years, but was lacking either the necessary aptitude or attitude to play well. The fact that I progressed so quickly really frustrated him.
I believe it was about 3 months later when all city auditions came up. I think I made about 4th chair. In following years I was usually 1st chair in the all city and all region orchestras. There was one other player in our town of 250,000 with about the same level of natural talent, and I almost always bested him. But I never had the focus or dedication to make to all state, and I believe he made it to 1st alternate one year. So basically I was sort of a big fish in a little pond.
I think my musical talent is above average, but I am by no means a superstar. Somehow I managed to become a professional musician and do pretty well for myself because I found a niche were I think I really fit in. When I was still active I liked to say I was pretty good at faking it. I was always aware that I was nowhere near as good as the people everyone wanted to perform with, but I was solid and generally respected.
I was also a lot more versatile than a lot of players. I consider versatility my standout quality. I don't enjoy playing the same style of music all the time and find it much more enjoyable to mix things up. This means I am not a great orchestral player, or a great jazz player, or a great commercial player. But I was comfortable and competent in pretty much all of these areas. So typically if one of my peers was a better jazzer, I was a better orchestral player. And if another one of my peers was a better orchestral player, I was a better jazzer, or better commercial player, etc.
My advice is focus on your own talents, interests, and path. Feed your hunger for musical growth and enjoy the ride. When you stop growing, it's very likely that the ride will be over. I haven't performed regularly since about 2008 and really have no interest in it. I was touring pro for over 20 years and had a blast, until I didn't. Then I did other things that were tangentially related like running sound, and had a blast for a few more years.