Like most things micro-soft and browser, this is a bit out of date. You aren't going to kill your page with the
* selector if it's used sparingly and / or scoped.
Having said that, you could probably could go crazy it with the
* selector as css selectors are evaluated right to left - meaning that each rule that ends with a
* will need to be checked for every element the page renders, making it the least efficient thing to end with. Combine this with using it on every selector and nesting it deeply and you probably could jam things up.
Separately, I'd assess the other part of the selector, putting a class on each
<td class='my-table-cell'> would make for a much nicer selector: more modular and therefore easier to re-use; easier to understand; and less specific.