It is indeed true that a lot of consumer grade routers use the same SSID for 2.4 GHz and 5.0 GHz. (The majority of them, I would expect.) It is also true that I have never come across a device that does not work because a 5.0 GHz network is present. Wifi devices connect to whatever network they can use, period. It “just works.”
So, for all intents and purposes, for pretty much anything with wifi connectivity that only has a 2.4 GHz radio, whether or not there is a 5.0 GHz network as well and what that network’s SSID is, is utterly irrelevant. With the exception of the Anova, that is.
The Anova does not work in the scenario outlined by @docj, even though that is a very common scenario for home networks. Moreover, the way to work around the problem is complex and non-obvious to the average user. That’s a design fail on Anova’s part.