MikeJones careful, your code also removes the "Tags" link below "All discussions", making it impossible to access the tags page. This might not be the intended behavior.
It could also hide links to the tags page inserted by users on the forum, if using relative links (like [url=/tags]click here[/url]
). If this happens it might cause headache to the forum moderators once someone encounters it and can't figure out why their link isn't rendered.
To hide only the "more" button, I suggest using:
.item-moreTags { display: none; }