Wi-Fi connection stays active when mobile hotspot is activated

[belegdol]

Hello,
since upgrading my Zenfone 8 to Android 12 I am experiencing the following problem with my mobile hotspot: when I activate it, the Wi-Fi connection does not disconnect, which results in the hotspot traffic still being routed via the wifi connection. This means that I have now explicitly disable wi-fi in order to get a working internet connection if I am still within range of an AP.
If this is intentional, I am not sure how this design decision was made. If I am within the range of my wifi, I would only need the hotspot if the wifi connection is malfunctioning, otherwise I could just connect my devices to the wifi access point directly. Moreover, how can the phone be a hotspot while being connected to wifi at the same time? Does it have two 5 GHz radios?
ETA: I looked a bit closer and the hotspot does fail over to mobile data once the "this network has no internet connection" notification appears. The issue with this is that it can take a while for this to happen, or the wifi connection might just be slow but not completely offline. Why would anyone pipe the wifi traffic through the smartphone anyway? I can imagine this being some odd sort of range extender, but I would also imagine that using a phone as a backup for a failing DSL/Cable/Fiber connection would be far more frequent.

[laci_kara]

1. Mine did this on android 11 too.
2. You may not want to share the wifi network of the house/office. Instead you can temporally give access to one or more users (routing wifi), even controlling how many clients are allowed, or block access any time. So it is rather a smart thing.

[belegdol]

Good point about Android 11. Now that I think about it, it is possible my Asus was doing it as well. It is just that disabling WiFi was easier in android 11.
As for using the phone as a gateway, you could achieve the same by setting up a guest network directly on the router. In general, I am not saying that there are no use cases for piping the hotspot traffic via WiFi. I just think than these would be far less common for an average user than the case of dealing with flaky fixed internet connection.