In just the same way plenty of people now don't know about what the unions then went on to create or enable. Spanish practices, crippling national strikes, the near inability to fire poorly performing staff, closed shops and intimidation of non union labour.

Many of these rights were also secured because the awful production line jobs were sent overseas (cf Bangladesh). Unions were a powerful force for good - but they also created huge problems in some countries once those rights had been one and they failed to modernise. Modern trade unions are again a powerful force for good, but those are the ones that aren't going on strike all the time and hardly anyone has a problem with them.

(From a very UK perspective)