That conclusion the article makes is not supported by the data - it's just speculation.

In my opinion, the decline in worker unions has been largely due to the relocation of factories abroad.

A nation without its own manufacturing based and non-existant import protections will of course lose union jobs.

Europe has high import tariffs that protect their own agriculture and manufacturing base (as well as raise the cost of goods). ...but that's the trade off.

Blaming some sort of corporate culture seems agenda-driven speculation.