> Silos are standard in all big organizations, full access is/was the exception in Amazon. Why should it be the corporation's duty to make it easier for employees to organization a union if it's not something that the executives deemed in the best interest of the corporation?
Nobody's forcing Amazon to not be siloed, but now they are losing a competitive advantage, because this disrupts communication within the company. There's a reason for why its leadership made a conscious choice to not be a siloed firm - and its because silos are less efficient.
It's much like a repressive society that shuts down the internet, because people are using it to organize against the regime. Sure, it's free to do so, but this has negative consequences for its ability to conduct bureaucratic and economic activity.
The difference between a government and Amazon is that Amazon does not have any control over non-work communication channels their employees use - so this move isn't even going to help much.