Board Thread:Support Requests - Designing Your Wiki/@comment-4339465-20200319190217/@comment-9605025-20200320152703

Technically, yes. But since they asked for a specific page, I am assuming there is a particular reason they want to hide it (ex. popular spam target or "controversial" topic). As long as you can give a good reason why Fandom should make an exception, they will likely allow it.

There was an example quite some time ago (I can't find the actual thread unfortunately) where a wiki had a rare use case for subpages in which having breadcrumb links in the page header actually made things more confusing. In that particular scenario, the got the "okay" from staff to hide the links using CSS.

An example of my own, the wiki I admin is old and uses a "not officially supported" extension. A while back, some of the changes Fandom made interfered with one of the features. Staff allowed me to write my own JS to correct the inadvertent changes even though such modification to the interface constitutes a violation of the customization policy.