A few days ago (yesterday), a sorta long time member (registered May 13) decided to quit. While quitting from a community usually invites tearful long have-a-potato messages, this young member decided to take his work with him. Which again gave the community some extra work: That of retreiving said mods.
According to a Moderator: "You should avoid removing content posted by yourself if people rely on it (releases, etc.)."
Is a standing rule. Which hasn't yet been written down. Plus some licences also specify that you cannot take down a project which has been open-sourced
If you want to work at building mods/textures/custom games/ whatever, remember. Your work is your ownn and you will be credited for it, but it also belongs to the community and they have a right to accessing your work when you release it, like it or not. And once it is released, no existing copy of it that people rely on can be removed, unless there is a grave reason for doing so.
However, the world is round, the sun rises in the east and there are stupid people that do it because they are stupid. Or something.
Now, what can we do in case a dev decides to ragequit and take his work with him? For this: some of us have thought of the following pointers:
1. Make this an essential rule "You should avoid removing content posted by yourself if people rely on it (releases, etc.)." Edit the rules tab at the top of the page to include this.
2. Make it obligatory for every mod to use the mod repository (https://forum.minetest.net/mmdb/) for uploading mods. This has many benefits over the old github zip release and the forum attachment thing. For one, there will be greater incentive to develop the mod download thingy in the game. With auto-updating mods, the game will become much cleaner.
3. Remove the ability to delete forum attachments, or the ability to remove mods from the repo (if there is already a feature to delete mods at all).
For me, I think that forum attachments are nasty, and that updating the repo and tools in the game are much cleaner ways to install and use mods.