Would be more meaningful if they quit in protest to a lower paying job. This type of protest is merely exercise or a routine jog.
Unions are rather weak when they can't prevent employers from hiring strikebreakers.
The common factor is that it's not enough to refuse to work, unions must be able to ensure that no one does the work.
Often the barrier is natural, such as with folks at Google who built the systems and are (collectively) the only ones who can keep them running without significant interruption. By what authority, for what compelling reason, would you abridge their freedom of association (or in this case non-association)?
But earlier you claimed they were "the only ones" capable, and that I wanted to abridge their freedom of association. I disagreed with both those statements.
Now that you've restricted your position to acknowledging a reasonable cost/benefit tradeoff for Google, I agree.
No, I claimed that they were the only ones capable of running the systems without significant interruption. Others can be trained up, but it would take months and there would be some failures along the way. You're the one whose argument has been changing, since you started with the presumption that strikes' effectiveness relies on explicitly excluding others (e.g. via law or force).