I don't understand the problem, You've got a perfectly well working product, just without the Internet access. If you don't want to connect it to use the advanced features, just unplug it and use the mirror in the way you like.
Some people enjoy having some unique tech are they wrong to be upset when the product they paid for doesn't work? It's dumb that the error takes up the entire mirror so by sharing posts like this on social media it encourages the makers to fix this flaw by using public pressure.
Who said it doesn’t work? It’s telling you to connect to WiFi. If you wanted to use the smart features, you don’t care if it’s blocking the mirror because the point of this device is not the mirror.