In several edits like this one you removed the distinctive gender word from the label, causing all parts in the 'has parts' section of the next upper level (in this case US Open 2018) to look the same. As a consequence, a reading visitor cannot know which part to click as they all look the same.
Topic on User talk:Matěj Suchánek
I went through all edits since May and restored {'vrouwen', 'mannen', 'jongens', 'meisjes', 'enkel', 'dubbel', 'mannenenkel', 'vrouwenenkel', 'jongensenkel', 'meisjesenkel', 'mannendubbel', 'vrouwendubbel', 'jongensdubbel', 'meisjesdubbel'}. Nevertheless, I think using brackets in labels is ugly anyway.
Thanks for the restore. The brackets format is not my decision. It was initiated here at nl-wiki many many years ago, a long time before I started working on tennis articles. I just continued it. Note that the French wiki and the Spanish wiki use brackets too. Why would you interfere in other language's label titles anyway? When filling in missing labels of other wiki's, I abide to their local habits; even with the wide dash of the English which is on no-one's keyboard, and the slash of the Germans which causes an uncomfortable deeper level in the article name, etcetera.
I don't mean to interfere that. Still, this is Wikidata. Labels are bound to the language, not Wikimedia projects (which only act as a good source of them).