Yes it can happen. Want they know how to do one day, they may not know the next.
Mum who has always done the laundry, is starting to have issues with the washing machine, insisting its broken. The simple microwave I bought them, with less buttons, Mum forgets how to use, and will put something on for 10 mns instead of 1mn.
With Mum & Dads TV, having a remote to turn the TV on, and Sky TV remote was too complicated.
I took the remote away, and taped over the buttons on the side panel of the TV except for the red ON/OFF switch.
Now they only use the Sky remote for switching channels, but ocassionaly will switch the Sky decoder box off, and neither of them can figure it out.
If your Mums TV remote has lots of buttons, you may need to consider a simpler universal TV remote.