[...]
> I do agree that anything non-essential (even if it's just a presentation
> menu that doesn't affect builds) must be default n.
It's tricky for "make oldconfig" when introducing a new "menuconfig"
around some previously existing "config"s, because just accepting
the default for the new option then causes previously selected
ones to be silently dropped. But I don't know a perfect solution
for that. Perhaps we'll just have to live with it. Or perhaps a
warning message along the line of "deselecting option xxx" would
be in order.
[...]
It's actually the other way around, all those options now tucked
underneath the menuconfig were previously directly visible, so
selecting "y" (either explicitly or by default) makes everything
work as before while "n" very conveniently skips them all.