I've never (knowingly) encountered a z-Series. I did encounter one of a former employer's System/370s: a 3090, quite a big bugger but a disturbing lack of flashing lights. It was mostly featureless except for the typical clunkity IBM on/off switch. I was allowed to stand within arm's length of said switch, which seemed rather ill-advised.
I'd love my own PDP-10, harbouring a fantasy that a KS10 CPU is small enough (i.e. about the size of a large fridge) that I really could have my own 36-bit mainframe. Then I discovered how much power it consumed. Given that I complain about the ~120W my i7 uses at full pelt and a PDP-10 CPU is about 200 times that amount... maybe not. I think I'll stick with emulators, which actually was the last time I encountered MVS. PDP-10 operating systems were cool and highly influential; MVS is... something that occasionally needs to be experienced to keep things in perspective, I think.
And yeah, firmware is subject to the same problem as the rest of software: programming and IT in general aren't really considered to be "proper" professions by management types and can therefore be tendered to the lowest bidder. And it shows. Firmware is worse than most as it's largely invisible, and so are its indiscretions. I suspect that's due to much the same reason you pointed out, incompetent people surrounding themselves with the even more incapable.
The Linux/FreeBSD thing gave rise to the interesting treatise, The Cathedral and the Bazaar, though I think that's not any sort of schism and there seems to be a lot of mutual respect. Maybe that's where GNU went wrong.
