I dunno, I've done it myself, and I would say that it's qualitatively different than other "banging your head against the wall" software development. At least it's an order of magnitude more painful, due to lack of integrated tooling, questionable documentation, and a more delayed feedback loop.

Single-threaded kernel bringup is easier than most distributed systems though.

Funnily enough, when I was writing one in Zig for x86 I actually was the one who found a bug in (I think) 0.11/0.12 where packed structs broke when you assigned to their fields (and I also found that the `.interrupt` calling convention was a todo item in that version). GDT/TSS is always, always one of the most annoying parts of an x86 OS for me, because all of it is so tedious and unnecessary, and I wish Intel would just get rid of IA32 mode already, or add some kind of bit in CR0 or CR4 which caused all that extraneous setup of legacy structures to just cease to be. RISC-V is so, so much more pleasant to get started with. Limine helps regardless of which architecture your getting going with; it's pretty much my de facto bootloader at this point.