The traditional response to that was violence against scabs, for better or for worse: it keeps people from breaking picket lines even when otherwise willing.
> The traditional response to that was violence against scabs
And how are you going to do that when the scabs are in India? Unions work in “physical” domains (like plumbing, factory work, etc.), not so much in “virtual” domains where all you need is a computer to do your work and there’s an entire world full of workers who would think they’ve died and gone to heaven if they could make half your salary.
This photo in particular captures something of it: https://en.m.wikipedia.org/wiki/Ford_Strikers_Riot