In 14.1, on premise, how can I conditionally "hide", or make collapsible, a section? I can see how to do this for a subpage, but not a section. Any help is appreciated.
Unfortunately we can't do that - sub-pages are the only things with "display conditions" or security-access rules.
From 14.3 on we can (manually) collapse/expand sections, I'm not aware of doing that in any other way than the user clicking on the section title though.
as Dave says, this isn't something configurable right now.
There might be an unsupported hack but I'd recommend voting these two up
Ability to Collapse any section on an object page
Display Conditions for Sections
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