My husband has the same technology issues with his laptop and cell phone, and he rarely used them before he developed dementia, either. He doesn't even know that the small, plastic rectangle on the table is a phone. If he did try to use his devices, it was usually not good. He'd do things like answer spam email or reply to business texts he had answered months earlier. Little by little, I've been finding ways to distance him from his devices.
For example, when he couldn't remember his password to unlock his computer, I told him it was probably broken, and I put it away "until we could get it fixed." He has forgotten about it.
I erased contacts from his phone, and, when he complains he can't find them, I offer to call family members on my phone. For important business contacts (doctors, financial planners, etc.), I suggested he switch contacts to my phone "because it works better."
If necessary, I used a Power of Attorney we had done years ago, to have permission for access.
@geppetto , I hope some of this helps, though I'm still learning, through the wonderful support on this site, that things will keep changing.
I found a wonderful quote a while back - author unknown - that serves as a good reminder to me to go with the flow:
"Blessed are the flexible, for they shall not be bent out of shape."