Would there be any reason not to have a Hub 5 mounted horizontally? It’s in modem mode. Maybe ventilation but it doesn’t seem like it gets that warm. Was thinking of getting a tray or cable organiser that’s big enough and mounting it under the desk.
The hubs don't do as much work in modem mode so don't get that hot anyway.
If there was any concern about heat then a small USB fans with rubber feet next to it would sort it - I do this with a couple of devices on a rack shelf that would otherwise get quite toasty and they run very cool.