Steve Lawson plays (mostly solo) improvised bass guitar. That doesn't mean he takes an existing tune and plays a solo over it. He comes up with new pieces of music each time. His more recent recorded works are one-offs that he won't recreate exactly in a live setting. As well as being an amazing player he also writes very well about what he does. Check out his latest blog on his creative process.
Image from Steve's site
I haven't seen him play recently, but I have been to several of his gigs a few years back. One of those was with fellow bassist Michael Manring. The two of them blew me away with their playing and creativity. They improvised duets on the spot that went in all sorts of directions. We're used to hearing people recreate what we're heard before, but these tunes had never been heard. It's a different musical experience and it can be hard to adapt to. People like familiarity, which is why it can be hard for bands playing original music to do well when they start out.
Steve works independently of record companies, so he can do what he likes. He experiments with different models, such as offering subscriptions where people can get all the music he produces.
I only discovered the whole concept of solo bass accidentally. I was looking for podcasts about playing bass and discovered one by Jeff Schmidt which led me down a rabbit hole that led to Steve, Michael and some others. The bass is a little like the cello in having a human voice quality that appeals to me.
Steve's wife Lobelia is a singer and songwriter who I have seen perform with him. They make beautiful music.