Are fabric or rubber resistance bands better?

It depends on the exercise. Across specialist communities like r/StrongCurves, the strong consensus is that fabric (cloth) bands are far better for lower-body work such as squats, glute bridges and lunges because they don't roll, slip or pinch the skin. Rubber/latex loop and tube bands remain the choice for upper-body work, pull-up assistance and full-range movements because they stretch much further. Many reviewers simply own both types.