It is and there is no reason not to do it this way just because it has been around for a long time.

However, for accessibility reasons, Son of Suckerfish[0] works a bit better. It moves hidden items out of the viewport instead of using display: none, thus making the menu usable to screenreaders users without them having to "hover". It would of course also be advisable, to expand the :hover to also inlclude :focus.

[0] https://www.htmldog.com/articles/suckerfish/dropdowns/

...and that works all the way back to at least IE6.