gmsh produces bad artifacts when tesselating a trim curve
When tessellating the attached STEP file (tube.stp), which contains trimmed NRUBS surfaces, the generated mesh is generally of good quality, except in the vicinity of some trim curves, where the output is very bad (jagged border).
I have attached the original STEP file, as well as some screenshots of the resulting mesh.
The tessellation was performed using gmsh-4.9.5-Linux64 with Options -> Mesh -> General -> Element size factor set to 0.01
Worth paying attention to: the convex boundary between NURBS patches are very regular (bottom left of image) whereas the tessellation of the trim curve is very chaotic.