Ask HN: How to manage phones and PCs for elderly parents?

I have a friend whose parents are getting up in years. They're still functional enough that they want to be independent and surf the web, check their stocks, etc. He has some remote desktop software installed on their PCs, and antivirus installed and locked down. But they keep destroying their PCs with downloads, keep turning airplane mode on for their phones and can't figure out how to disable it, and recently his dad got in a cleaning mood and deleted a bunch of system files and bricked his machine. He's almost to the point of setting up an Intune tenant just to onboard and lock down his parents devices. Any suggestions on how to manage phones and PCs of the elderly to keep them functional but useful?