Yes, I do. I do that for ease of management so that I can easily know and control what is using what (I have lots of SSIDs and lots of devices).
If you choose to advertise the same SSID on both bands, which is perfectly valid, then I’m sure there would be some way of controlling which band is used on the client side (e.g. at its simplest disable 5 GHz on the client side) but I don’t know what the incantation is. Maybe use nmcli to look at 802-11-wireless.band ?
Adding: If you directly edit the xyz.nmconnection file, you may be able to add band= in the [wifi] section but I don’t know what syntax you need for the value. Also, if you edit such a file, you will either need to reload or reboot.