My question pertains to a set of vintage early 1980's LCD video games
more commonly known as the "Nintendo Game and Watch" series. For those
of you who are unfamiliar they were handheld (and tabletop) video
games of the early 80's that also functioned as a watch. They used
typical monochrome static LCD screens overlayed on colored backgrounds
for effect. None were backlit but some had a light diffuser window
behind the screen to allow ambient room light to shine through and
give the illusion of a backlit screen.

My question is about whether keeping these units powered on will risk
deteriorating the LCD screens and shortening their life span. I have a
game room set up with some of these on display with external 3V
alkaline battery packs powering them (to avoid damage from battery
leakage) so they can always stay on in the 'watch / attract mode' as
they were originally designed to do. Given these are basically the
type of LCD screens you'd see in a cheap drug store digital watch, will
keeping properly rated current applied to them cause potential
degradation? They are vintage and are collectors items (not cheap) so
I don't want to risk damage to the games, but they do look very nice
when functioning and with an ambient (LED) light source to illuminate them.

I've searched the internet high and low for info on whether the
non-illuminated, static, monochrome LCD's have a life span (natural
inevitable deterioration in proper storage vs accelerated
deterioration due to functional use) but my search has come up with
nothing conclusive.

Any thoughts?