> Manufacturing offshoring started in late 90s

Speaking as an Irish person who grew up in the 80's, this isn't true as there were loads of US companies manufacturing in Ireland back then. There were even clothes manufacturers until the mid 90s.

So I'd probably agree more with the OP here, perhaps the Asian outsourcing happened in the 90s (but even then, loads of my toys as a kid were made in Taiwan), but this has been happening for a while.

It's potentially related to the relaxation of capital controls that happened in the 70s.