Is the Tamron 17-28mm f/2.8 Di III RXD Lens sharp? This page visually answers that question. Shown above are 100% crops from a lab-captured 28mm f/3.2 test image. Observe the contrast and resolution of these results.
Is the Tamron 17-28mm f/2.8 Di III RXD Lens set to 28mm f/3.2 sharper than the Nikon Z 14-30mm f/4 S Lens set to 14mm f/4.0? The image quality comparison above also answers that question. Switch between the results to see the sharpness differences between these lenses.