> The <table> tag is for tabular data, it implies relationships between it's elements that are of utter importance for screen readers and machines.
Nope. The <table> element was originally defined as an all-purpose chainsaw for two-dimensional relationships. The browser crackmonkeys locked us into that in the late '90s, and we have to deal with it forever. We are stuck with the legacy of billions of old documents, and thousands of old HTML parsers.
The W3C is pissing into the wind by trying to rewrite history. They cannot simply wish away technical lock-in by putting a "TABLE elements are semantic" clause in a standard. That needs to be repealed, and the we-must-ignore-history children must be given a spanking and sent to their rooms.
What the W3C should do is define a "tabulartext" attribute:
<!-- A table of data to read -->
<table tabulartext>
<tr><th>Title</th> <th>Title</th></tr>
<tr><td>Data</td> <td>Data</td></tr>
</table>
<!-- Structural markup -->
<table>
<tr>
<td>{{left_sidebar}}</td>
<td>{{content}}</td>
<td>{{right_sidebar}}</td>
</tr>
</table>
If they did this, the screen readers and Alexa top 500 sites would
STAMPEDE towards a bright new future of accessibility, machine readability, and backwards compatibility.