I love Charlie Byrd. His music is called jazz and he plays a classical guitar with nylon strings.
Benedetto was one of the first who tried to make an archtop guitar with nylon strings about 20 years ago. He made one and I dont think the concept was a great succes.
Later my colleague Daniel Slaman began to experiment with archtop nylon strings and he seems to be pretty succesfull with that. Other builders are more traditional and offer besides some archtops also classical guitars which they call a nylon jazzguitar.
Recently I have built a crossover between an archtop and a nylon string for a client. Our goal was to have the feel of an archtop but the sound of a nylon.
We decided to make the top flat and braced like a classical guitar and make the back rims and neck like an archtop. All very high flamed european maple. Streching design and keep it traditional at the same time. Nicky Mooken wrote a positive review in Gitaar plus magazine.