Isn't Helium-3 mainly used for fusion reactors? So as long as fusion reactors are still just in an early prototype phase, such a mining operation is probably not really lucrative.
Personally I don't like the whole crypto coins scene much but if you're interested in an open social network with ties to crypto, have a look a nostr.
I think Stash should cover most of your points, except for the page-less scroll: https://github.com/stashapp/stash The only other software I know for this is Porn Vault: https://gitlab.com/porn-vault/porn-vault
If you want to delete something that is part of your Google account, then yes. Like your Gmail address. But not if you want to delete your account in an entirely different service, that only uses Google for the login. I guess the problem is, that Threads is perceived (and maybe also marketed) as an independent service while it's apparently just part of your Instagram account.
By that logic you'd have to delete your Google account if you want to delete any account for which you have used Google to login.
I'm currently looking for a software to host my images and I found this table quite helpful to compare features: https://meichthys.github.io/foss_photo_libraries/
While I agree that it is probably better to not defederate them right from the start, I believe that the Fediverse might not have that much leverage. This recent blog post about the history of XMPP describes it pretty well: https://ploum.net/2023-06-23-how-to-kill-decentralised-networks.html
As expected, no Google user bated an eye. In fact, none of them realised. At worst, some of their contacts became offline. That was all. But for the XMPP federation, it was like the majority of users suddenly disappeared. Even XMPP die hard fanatics, like your servitor, had to create Google accounts to keep contact with friends. Remember: for them, we were simply offline. It was our fault.
Of course it's different because this is social media and not just 1:1 privat messages. But for us to actually have some leverage/impact we have to generate a lot of (good) content so that Threads users will actually notice and complain if that content "vanishes". And at the same time we must not become too dependent on their content
lemmy.world is one of the biggest instances, so I wouldn't be surprised if the server struggles from time to time. Because of how the fediverse works, switching between local, all and subscribed doesn't make a difference. You still access the non-local content through lemmy.world because it's cached there.
There are multiple GH issues on that topic
https://github.com/LemmyNet/lemmy/issues/818
For me, saving a post also crashes the app. But when I open the app again the post is saved. So at least the saving itself works.
There's one small error in the list: The community link for Memmy points to the community for Mlem.
Do you have a source for that? I can only find info about it being used for fusion.