Systemd hate is about it consuming things, and doing things badly.
gens
Originally it was about code. Split it into reusable functions, and such.
SyStEMd fans don't understand, per usual.
Unix domain sockets, shared memory (classic and/or over anonymous file descriptors), file system in userspace, the (ms) ini format.
Was going to sleep when i wrote that.
Uds, shm, fuse for ipc. Ini for configs.
FF7 and supreme commander were complex. And devs then didn't have the tools we have today, not to mention game engines (there were, but not like today). And ps3 was a pain to program for. And, and...
I was gonna go with the other guys sensible answer, but i like yours more.
Having a company behind software means you can pay to have your bugs fixed. Big distros want that stability for their corporate customers. It's no secret or anything. KDE has sponsors, but doesn't have a direct relationship with a huge contractor like RH. Same reasoning for systemd.
Politics, basically.
Contrary to popular opinion, i'm gonna guess graphics driver. Specifically the shader compiler.
I measured my fridge. You could, in theory. Problem is that the motor in the fridge (and in power tools) is an "induction load", meaning it draws a lot more power in a split second when starting. Inverters have to be built with that in mind, or just stronger (killowats range).
So i checked the fhs. Doesn't say it is deprecated. V3 just mentions XDG and glib (the probable sources of such claims).
Hmm. I can't find ehere i got that from, other then it being more general. https://cscie26.dce.harvard.edu/lectures/lect02/6_Extras/ch01s06.html
Either way the whole point is to write programs/code that can interoperate and be composed. SysD programs comunicate over an "implementation is the specification" protocol, so they might as well be one blob instead of separate programs.