Eh, I wouldn’t call them assholes for that. I’m sure there’s a minefield of legal issues that could come up that is mitigated by releasing it to public domain. By the same logic, anyone can also take the code, modify it, then release their modifications with a copy left license.

How does this make them assholes?

I use nextcloud tasks and deck for keeping track of things. Tasks is great for checklists, calendar integration, reminders, etc., I use it for simple reminders like trash day, and things I don’t want to bother with making a calendar event for. You can have it make a calendar event, but I don’t. Deck is a kanban style thing with calendar integration as well, it’s a bit more job-task oriented so I use it to help me juggle tasks when I have a lot of projects that need keeping up with. Setting up nextcloud is way overkill for just those features, though. If you’re not looking for the other features of nextcloud, I don’t think it’d be worth it.

It is pretty easy to set up if you go the nextcloudpi route on Debian, you don’t need a raspberry pi. Any computer running Debian can do it, but you may need to install a few dependencies if you’re on minimal Debian that aren’t listed anywhere, at least last time I set it up they weren’t. But again, if you aren’t looking to use the rest of nextcloud, I wouldn’t go that route.

I would think that you could leave a Rosetta Stone with directions on how the data is stored and read. It wouldn’t take much, I think. “These glass things contain information, here’s how it is encoded. Here’s the requirements on reading these”. You could start off simple and have a rudimentary one that can be deciphered by hand that describes how to make a device that can quickly pull information from a few others that give directions on how to build another device to read the high capacity ones. You don’t need a specific filesystem or computer to read it, you just need to know how to decipher it and that it IS data stored in a certain way, not just cool looking glass art.