Amazon has been making serious strides in becoming the smart home company. Considering that company goal, its pretty obvious that Amazon would then need to purchase a successful, easy-to-use home-wifi mesh system to support all of those smart home devices being pumped out of the Amazon warehouse.
Currently, Eero can be used with any smart home ecosystem. As a user of Eero in my home, I’m not particularly concerned about Amazon’s acquisition of Eero. I in no way use Amazon’s smart home ecosystem and I highly doubt that the Eero devices would become walled-off from either Google’s or Apple’s ecosystems. The only smart devices that can be walled-off are 'change-of-state’ devices like lightbulbs, televisions, and thermostats. A ‘change-of-state’ device requires either an automated or manual input from the user in order to reach peak-functionality. A wifi-mesh system, on the other hand, simply needs to be turned on and stay on.
Eero is successful because it’s easy-to-use and requires very little input while setting up and almost no input after that point. Somehow, I don’t imagine an, “Alexa, turn off the wifi,” being a step toward easier-to-use functionality. Eero will no doubt continue to be a background system that just works on all ecosystems, now with more funding.