My dad dives double steels, in a wetsuit, with no BCD, and no SPG. That's old school, too. That doesn't make it a good idea.
What doesn't make old school a good idea is diving gear that you are not trained / experienced in using properly. The same can be said about doing technical dives without the proper background, or diving at all.
Some newbie somewhere is too likely to feel like "old school" is synonymous with "best" - which it is decidedly not.
There are a lot of varying opinions, including yours, on the board that would dispel that opinion. The parts of old school like good watermanship skills, good buoyancy skills, and good emergency skills, are always a good idea. The fact that they were absolutely necessary when dealing with the primitive gear used then is easily overlooked by someone using today's gear and training.
As am I. There has been some talk of people having only one second stage and no alternate. Maybe a silly question, but who does that who was certified in the last 3 decades? Understandable in the days when everyone buddy breathed for OOA and maybe regs had only one second stage.
Divers that enjoy diving old school. There are also younger divers that get a kick out of it now, which I am glad to see.
With the first regs, both double and single hose, there was not a port to put another second stage on, even if one could afford it. That all came later.
age and primary, no way would I ever consider this. It was proven many years ago that buddy breathing was dangerous without a lot of practise (with a number of lives lost due to it) hence why it was removed from most (if not all) OW training. Far easier to hand of a reg to them and make a relatively calm ascent while you are both breathing as and when you want.
Although there were a small number of deaths from buddy breathing gone wrong, the big reasons for the change to a safe second was the relatively inexpensive cost of a second second stage, and the hysteria surrounding AIDS and its possible transmission during buddy breathing, in hindsight it may sound foolish, but it sold a lot of seconds. The narrative for using a safe second has changed over the years. At the time buddy breathing was taught, the few fatalities associated with buddy breathing came up as an example to learn properly and practice. I never heard of a BB fatality happening in my circle, but that's just one data point.
I mostly carry a second second stage because no one is taught buddy breathing any more as a matter of course, but have been known to dive with one second when solo, or when old school with a like minded diver.
Bob