You're all correct
It's a file sharing system for people who like the multi device sharing of cloud but want to host it on their own hardware. For work it's good because we already have VMWare servers and storage on site so we can host it ourselves and it eliminates the data protection worries surrounding cloud hosting.
I thought that for home users considering a NAS it would be handy as you can use it to share files with your tablets/phones either using a website login or a native app. You just need to set up a user account and give it a password. File permissions work from there.
It does things like automatic photo upload from your mobile device. You can share files with other people by sending a link (which may be password protected, set to autoexpire, neither or both). You can also ask people to dump files on a share using the same "send a link" method and allow or deny file editing within that folder.
Basically it does a lot, but yes - their site is frustratingly opaque.
V13 apparently does end to end enryption and hosts Collabora which is a sort of google docs for Libre Office users - but I haven't tried any of that yet. Nor have I tried the built in chat/video calling stuff which is meant to replace skype/slack/etc with a system controlled by you instead of $potentiallyevilcorp
But, to answer the original question, it looks like no-one else is using it here. Still, it might be work having a crack at if you've got a spare couple of hours. The hardest thing for me was running into "too many redirects" after using cerbot to set up a free ssl cert. Even that was down to me being a total newbie at apache and I sorted it in the end.
