They should not be missing role="gridcell", and having aria-disabled="true" will tell Accessibility Insights tool to ignore color contrast requirements.
Before:
<td class="empty">31</td>
After
<td role="gridcell" aria-disabled="true" class="empty">31</td>
They should not be missing role="gridcell", and having aria-disabled="true" will tell Accessibility Insights tool to ignore color contrast requirements.
Before:
<td class="empty">31</td>
After
<td role="gridcell" aria-disabled="true" class="empty">31</td>