Whilst I wouldn't use the word 'devastating', this is certainly a well-written review pointing out the glaring flaws in this IoT device.

It's not devastating because there's enough 4- and 5-star reviews from people who have evidently overlooked these flaws (or who have iPhones or old Android devices that allowed setup to work). This word of caution is likely to get lost among the noise.

The author has done a steller job highlighting the awful quality and attention to security of an innocuous IoT device. Granted, a wifi-controlled socket is likely to only power a table lamp or something similar, so anyone brute-forcing the MAC addresses isn't going to do horrendous amounts of damage, but the inability to prevent someone doing this is a clear illustration of the little control the end user has over 'smart' devices.

Bottom line: if you can't root it, don't put it on your LAN.