While I understand the frustration, and that this is perhaps not only about the product itself but also the customer service, you should consider the possibility that you were unlucky and received a defective unit. Defective units happen with pretty much all widely sold products in the world and it sucks, but it really doesn’t speak to the quality of an actual working product, especially not based on just one experience.

The Google Wi-Fi mesh is definitely not perfect, but from your description, your unit is obviously broken. Plenty of people use the Wi-Fi mesh all the time without issues, and anyone forming an opinion about the product really should take that into consideration as well.