[doingtheiroming]

The answer might be in the article already. The proportion of manufacturing that is in industries like construction has increased versus heavy industry, semiconductors, auto-manufacturing etc. The reasons for a decline in productivity in those industries seems pretty clear. If you have to build anything in NYC or any big city, your people are going to spend a lot of time standing around waiting for things to happen. When you can't put a hole in the ground without significant paperwork, is it any surprise that it's hard to drive productivity increases?

The obvious contrast is Tesla. The level of productivity with which model 3s are built now is clearly a vast improvement over where it was and the improvements (single casting for e.g.) keep coming. As long as US / UK and EU manufacturing continues to substitute making things in factories for making them in the street, and heavy industry for light industry, it's hardly a surprise that productivity overall is going nowhere.