By teaching groups for Wiki editing I found WYSIWYG support for tables most important.
Even elder people I can get accoustomed to markups like bold, links, headers / TOC, bullets, categories etc without WYSIWYG, but not for tables.
Editing Wiki tables in Libre Office makes them huge and no longer editable manually.
So table support is not just an option but a minimum feature - the "condition sine qua non" - for WYSIWYG support.
tomte , Member 542126 in WikiMedia Deutschland