Why do instances not run ads?
It probably goes against the philosophy or whatever of FOSS or Lemmy itself, but why not be a little evil so that you can actually sustain yourself? Donations can bring us far, but small non-intrusive ads can be a bliss in the skies for the people actually hosting the instance. Especially if there are millions of users uploading thousands of images and videos. This is extremely expensive.
Is running ads really that taboo?
EDIT: some people seem not to get the point of "millions of users", which presumably includes non-techies that do not use adblockers. I mean that without ads (or mining?), no instance would be able to scale to the point where it can compete with Reddit for example. If you were to want that. And not for profit, but solely for sustainability.
Text is cheap. It doesn't cost a ton of money to run these instances at least not yet, so people can do it as a hobby or with a few supporters.
It does however pay to ask your instance admins what their plans and policies are for moderation, defederating, finances, backups, having a money buffer in case things need to be spun down, and having multiple admins in case of disaster.
The image hosting might cost a bit though. Maybe instances can farm them off to places where storage is cheaper, or have premium membership options that includes image hosting. I would happily pay an instance a small amount to cover the convenience of being able to add images to posts and comments directly.
Sure! Reddit survived for a good long time without their own image hosting though. We'll see how the Fediverse handles it.