There are reports on reddit from people who have had their lighthouses on 24/7 since they bought them in 2016 so I'd say you're fine with those.
I leave only a couple of my PCs on during quiet days to minimise my power bill. The headsets go into standby mode after a few minutes of inactivity, and Springboard will play idle videos (by default) though that has nothing to do with whether or not it will play up.
At night I turn everything off at the power point on the wall, apart from the security system and the fibre internet ONT box.