Is all hernia repair mesh synthetic fabric?

No. There are many different kinds of mesh available for hernia repair. Some products are derived from animal products, or from cell culture products. Each product has specific uses, so talk with your surgeon to see what meets your needs.
Not necessarily. Most hernia repairs are done with synthetic mesh. They last longer and provide better results than biologic mesh. Biologic mesh tend to be made from some skin or tissue derivative. Basically biologic meshes have higher failure rates than traditional synthetic mesh.