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'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.
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/
You might want to check out Foxhole, it ticks plenty of boxes on what you've described, but it's more on the action side. It's a MMO combat game with a persistent world reset between every "war" (each one takes between two - several weeks realtime), players need to work together on fighting the other side, fortifications, logistics and strategy to defeat the enemy. It's pretty fun, albeit the camera angle gets a while to get used to.