Leave Airport Express 2 as Airplay only and no wi-fi on or turn off?

I have three Airport Express v2s I use for Airplay. The Wi-Fi is off and they are no longer network routers and only link via ethernet to my home network for Airplay. So essentially they are ethernet Airplay receivers.

I use them in an earlier firmware to ensure they play only 16/44 lossless as Airplay 1 only for Apple Music. I also do not need Airplay 2 in the home. I only use these one at a time (which is leading up to my question).

I use one in home office during day.

One in bedroom before bed.

One in living room in evenings.

So I turn the office one on at start of day and off at end using a multi outlet with a manual switch. The one in bedroom is in a smart multi outlet and I turn that on and off by voice. I generally leave the living room one on all the time but, it too can be powered on or off with an energy saving tap triggered by the stereo turning on.

The question is this: I do all this to save money and not waste electricity. However, considering the use of these units (they run very cool to touch with no wi-fi), just for Airplay to DACs to stereos, am I damaging them by turning them on and off 4-7 days a week? OK, sure, maybe yes but, since they do much the same as a Belkin Soundform Connect, maybe it is OK to turn them off or, maybe just leave them on and pay the 50 cents a years (wild guess, I dunno).

Please don't guess an answer. If you actually know, then I would be interested but I am not interested in any “I heard” or “Electronics should stay on all the time because I am a Boomer and told you so” because, that is the nut of this question so you saying that does not help. 🫤

I like facts… 😂