Is the Canon EF 100mm f/2.8 USM Macro Lens sharp? This page visually answers that question. Shown above are 100% crops from a lab-captured 100mm f/11.0 test image. Observe the contrast and resolution of these results.
Is the Canon EF 100mm f/2.8 USM Macro Lens set to 100mm f/11.0 sharper than the Canon RF 100mm F2.8 L Macro IS USM Lens set to 100mm f/5.6? The image quality comparison above also answers that question. Switch between the results to see the sharpness differences between these lenses.