CSS support can at times be spotty. however, AFIK, "text-decoration:line-trough" only has minor bugs.
Internet Explorer for Windows versions up to and including 6 place the line-through line noticeably higher above the baseline than other browsers.
<strike> and <s> may still be supported tho. much the same way <font> is deprecated, but you can still use it.
As usual, that you can still use it doesn't mean you should. Tags convey semantic meaning. Usually a strike through mean information that was deleted ( in fact there is a <del> tag, and <ins>)