Here's a New Yorker article that I bookmarked years ago that also questions the efficacy of back surgery for chronic pain:

https://www.newyorker.com/magazine/2002/04/08/a-knife-in-the...

From the opening:

Last year, approximately a hundred and fifty thousand lower-lumbar spinal fusions were performed in the United States. The operation, which involves removing lumbar disks and mechanically bracing the vertebrae, is of tremendous benefit to patients with fractured spines or spinal cancers; more frequently, however, it is performed to alleviate chronic lower-back pain. But how effective is it? That’s a question that many of the doctors who perform the fusions, and the insurers who pay for them, appear reluctant to ask.

In addition to the nexus you point to, it's worth mentioning that for a lot of back pain, we have no idea what causes it, or why it goes away (if it does). I suspect a lot of it is pressure from individuals wanting their doctor to do something to help them with their debilitating and mysterious problem.

Source: I talked my dad out of a spinal fusion. I'm still not sure it was the right choice.

Start at 2min08sec:

https://www.youtube.com/watch?v=NyugCJ40IIw

“You’re using a clothesline as a flagpole”.

Is what you are claiming still accurate today? That Cochrane review is 15 years old, a lot has changed.

Spondylosis (vertebrae wear) has a primary cause, which is more often than not a herniated disc above or below that vertebra.

Unless there is some extreme space constraint most Orthopedists or Neurosurgeons would attempt an artificial disc replacement prosthesis instead of vertrebra fusion.

Unnecessary/ineffective fusions are still happening all the time. My Gf is a PT and unfortunately had to work for one of the surgeons for a time, as recent as 2 years ago. So perhaps this is a regional issue, but there's still not much pushback from payers in hundreds of cases yearly. Perhaps 2020 may be different due to COVID reducing procedures in general.