Missing Productivity Growth

There is no evidence supporting this claim. Productivity has always been mismeasured. No compelling evidence that this has gotten worse.

A number of papers debunk this idea, eg. Syverson JEP 2017. There's surely mismeasurement, but v. unlikely the primary explanation for trend

-see background information here
-see background information here

Requires mismeasurement problems to have grown over time. Mismeasurement may have increased slightly, but only slightly in my view.

Productivity has slowed down across countries and industries and it hasn’t been worse in places we think are most ripe with unmeasured gains

unaware of decisive evidence that this is biggest explanation for this period

It's a reason but I'm not sure that it is the biggest reason.

Mismeasurement has always been a problem. Retirements of Baby Boomers may be a new factor at this time.

-see background information here
-see background information here

See RJ Gordon on this topic.

Mismeasurement is a factor, but there are others, such as an aging population, climate change, resources for homeland security, and war.

Mismeasurement plays a role but not sure it is the biggest.

It may be a factor, but the productivity slowdown is widespread, and nothing indicates that mismeasurement is the most important factor.

The slowdown requires a worsening rate of mismeasurement (2nd derivative) and the research is clear that this is not the case, see links.
-see background information here
-see background information here

It is clear that this understatement exists. The magnitude is far more uncertain.