Protests don't work if you do them quietly in your corner without affecting anyone in a meaningful way.
It's also likely that people who saw this might now not want to be involved at all for fear of losing their job.
This action likely did nothing but make it less likely that anything will change, and been the absolute worst way to attempt to persuade people.
(Read the link. This is all about who's the real employer in indirect-employment situations.)
[1] https://www.morganlewis.com/pubs/2024/03/nlrb-blocked-from-i...
It also doesn't fix the problem where a number of contractors sue you even if they might be wrong. It could very easily be a class action lawsuit like the one that cost Microsoft a lot of money. They could use those rules as a start and then throw a few other things together such that Google thinks it might have a problem in court and wants to settle rather than risk getting sued by every single contractor.