You can find the idle power usage for sonos products here Sonos Power Consumption While Idle.
Which for a Sonos Beam, if I understand correctly how you to do the calculation, means that if it is idle overnight for a whole year its annual comsumption would be 6.3W * 8 hours (roughly) * 365 / 1000 = 18.4Kw which at current UK prices amounts to around £5.15. Which is not much of a saving if, and no-one can quantify this, it shortens the life of a product.
Idle is defined as audio muted or paused on all players in the household for at least 3 minutes, and no audio signal is being sent to a line-in connection or home theater player (in most cases, this means that the TV is off).
Which does imply that a device not being used during day, whilst another device is being used, will be consuming more than its idle value. Also for soundbars turning the TV off as opposed to standby should be considered, subject to the same issue of power cycling impact.
So, I suspect that the approach of turning off little used devices as suggested by @Kumar and @amun might be the better approach.