By "basic table editing", I mean generic workflows not specific to Wikimedia projects. By "support", I mean make it possible, not necessarily user-friendly (although that's a desirable goal).
This includes:
Rearranging rows and columnsCutting and copying parts of tablesPasting parts of tables as new tablesPasting parts of tables into an existing tableAdding row headersNavigating between cells in a table using tab or arrow keys
It doesn't include the following (although they're desirable goals):
Making tables sortable- Coloring table cells
- Making table controls which already exist more user-friendly
- Editing tables made up of templates
Finished tasks are struck