A properly lock-free architecture wouldn’t have spin-locks, no?

A properly lock-free architecture is a spin-lock :-)

spin locks prevent forward grantees, e.g. when the thread is scheduled out (or serves an interrupt), no other thread can make progress. Lock free allows progress - there is no exclusivity. Of course if working on the kernel and controlling the scheduler, etc. the restriction does not apply immediately.

Realistically though, lots of lock free employs copy-on-write or rcu.

of course, no lock.

I have written quite the fair share of lock free code (back then when it was new), and generally enjoy writing it (to this day). Yet, for most folks it's just too hard to reason/understand/maintain it.

Just a note, lock free is a lesser requirement than wait-free.