This is so true. Finding an electronic item that works for Grandparents is nigh on impossible.
I was looking for a simple Grandparent radio, which basically had on/off and a few preset station buttons. Very difficult to find - they all have equalisers and flashing lights and small buttons and hard to read text.
Same with a mobile phone: if someone invented a Grandparent Mobile with the ability to dial 5 numbers and that’s it, they’d be laughing. I guess you could make an iPhone/Android app where there were just 5 buttons with people’s names, but even that may be one step too far.