No.

https://www.nlrb.gov/strikes#:~:text=Strikes%20unlawful%20be....

> The U.S. Supreme Court has ruled that a “sitdown” strike, when employees simply stay in the plant and refuse to work is not protected by the law.

Also see https://en.m.wikipedia.org/wiki/Sitdown_strike#:~:text=A%20w....).

When the Supreme Court rules on this topic specifically, union lawyers are going to be fairly clear about the consequences and advice strongly against it. Whoever organized this at Google either didn’t do a basic Google search or didn’t care about very clear consequences.