If being a profesional bassist was easy, more people would do it. I'd guess it's 10% skill and 95% luck and 15% having good math skills.
I spent my career designing pro audio gear. In that line of work, while I didn't hang around big name musicians every day, I did spend enough time around enough of them to notice a strong trend about the "luck"/"who you know" comment that comes up pretty often.
We all are born knowing 2 people - our parents. Some of us have siblings as well, but past that, we aren't born knowing hundreds or thousands of people. Most of us end up with networks of people that we know - some small, some big. How many people you know, and how many people there are that have positive impressions of you are largely your doing.
When I've chatted with famous musicians (and engineers, and producers, etc), an interesting thing happens most of the time - despite my being someone that is not at all "famous", the famous person is often very interested
in me - if you looked not at what I'm wearing, but instead paid attention to the body language, and listened to the questions and answers, you might get the idea that
I was the famous person - the interest that the "rock star" has in who I am, what I do, how I got to where I am, etc. is a genuine thing. People that "know a lot of people" know that many because they go out of their way to find out what makes that person tick - they have a genuine interest in other people and are great at networking.
If you're trying to make a living at playing music, you never know who is the person that's going to be key in your next break (you don't get just one big break, you get a lot of little ones that add up over time), so you need to treat everyone you meet like they're important, because some of them will be. Luck is not luck - it's good people skills pursued over time, and when the opportunity arises, being able to perform your craft above expectations that gets you where you end up. I have a career of sorts as a volunteer musician in churches (long story left out for brevity). Applying what I have learned from the "pros" has made a big difference in the opportunities I have had doing that.