Why would I discount the most popular applications of the kernel? That is almost the whole userbase

That is an entirely different argument which I did not contest and the comment I have answered to did not make

EDIT: Although, it depends on what we define as “bigger”. Binary size is certainly bigger, but user adoption is abysmal comparatively.

But what about Linux distributions compiled without GNU tools? Most popular Linux distribution’s kernel currently is compiled with Clang, not GCC, and as far as I am aware does not include anything from GNU. Of course Linux is historically influenced by GNU, but in current day and age they are orthogonal

It has built in package manager now (winget install Mozilla.Firefox would install Firefox on clean Win11 installation).

how do things like the feeds work?

So what actually happens under the hood is when one instance communicates first time with another instance it builds some local cache of that remote instance. Then, when you open “All”, you get everything from your local instance + things cached/requested from other instances. Admins can defederate an instance, in which case you would not see anything from it.

Since there’s no algorithm is everything from Lemmy.world only going to show up on the popular feed (if I’m on that instance) or can other things like lemmy.ee or whatever also show up?

Everything federated will show up.

And can I comment on posts from a different instance or does that vary per instance?

If federated, you can both see and post both posts and comments on any instance from your home one.

could Lemmy theoretically allow content from those instances to be cross-posted here?

It could. More than that, Mastodon users currently can both subscribe to Lemmy instances and post/comment. It looks kinda weird since they mention post author/community or whomever they answer to in a comment, since they see it as if it looked like Twitter.

It has currency conversion, but it expects specific format

I see, good to know. I didn’t know about Tailscale so wasnt aware that it is a frontend for WireGuard. Although have to comment that ZeroTier is its own protocol

How is Tailscale different from ZeroTier in this setup?