There is a finite amount of them - 2^32, some 4.3 billion - the limitation stems from using 32-bit values to express them. We cannot have more added, as the "capacity" of the 32-bit IP address value to provide different numbers has been exhausted by "assigning" these blocks of IP space - back in the old days of the Internet, large blocks of IP space were given to large organizations (such as Xerox mentioned in the article), now cloud hyperscalers are buying them back at a premium so their customers can use it to host things.
I don't know about that, the smartest man in the world can't seem to stop posting while multiple distinct sets of complete idiots have managed to take over Afghanistan in the past two decades.
I've read about a hundred of Rachel's posts and never thought "but who/what company was this actually, specifically, by name", just enjoyed the stories. I mean yeah something something facebook, big places needing big troubleshooting, but in the end I think it's irrelevant to most people, as most people don't work in SV.
bash (and other shells), coreutils, pipes, git, text/cli utilities etc. work just fine on WSL, I'd call them Linux tools. My in-shell workflow consists of using mainly those + VSCode (with the WSL plugin) + ssh'ing somewhere now and then, and it's entirely sufficient for this purpose. I haven't tried running typical webserver/db services on it though.
They were quoting "The Matrix". But you're probably correct, even in the movies the existence of "The One" was a pretty serious security bug, and the entire need for "agents" was a workaround for other bugs.
It's a disassembler/binary analysis tool, widely used for creating, for example, cracks/executable patches for games and other programs. https://hex-rays.com/ida-pro/