I am very peripherally involved with XR UK (Extinction Rebellion in the UK), and they have some custom software that does various administrative things.

I wanted to nose around, as I do with many bits of software, but found it's not open source, which surprised me, as it's part of an effort to use a suite of open source tools (mattermost, discourse, etc).

I asked about it, and got the "security through obscurity" argument back (what if the government can see it!!).

*sigh*