>Each consecutive job hop past 15 years got me better pay, better benefits and sometimes a better job (sometimes it was equaly shitty as the prevous one but for better money). This does not happen for unionized workers.

As a counter-example to this specific point, the Screen Actors Guild does a tremendous amount of work to raise the pay and conditions of the median earning actors, without preventing the highest performing members from negotiating compensation in line with their ability to contribute to the success of a project. We can have our cake (collective negotiation) and eat it too (million dollar+/yr IC roles).

Other notable examples; State bar associations (lawyers) and the American Medical Association (doctors).