While this technology has its benefits, different devices at home have different reaction and response to changes in signal strength and quality, and it’s almost impossible to predict if they will make good band choices due to the interaction between the devices and the Wifi router. Some smart home devices also recommend that band steering is not used due to various reasons such as needing a constant consistent connection, ability to only connect to a particular band, registration of the respective MAC address, etc..

Example:

As single SSID is used, the device may remain on a weak 5GHz network  instead of switching over to stronger 2.4GHz network.