Tell that to all those Mac, Linux and Windows users on their daily desktops and laptops.

Almost none of them have even ECC memory.

Memory has much fewer “moving parts” than disk. You cannot get bad “memory cable”, and (AFAIK) there are no cases when overloaded power supply caused memory errors,

Obviously it's not connected by cable, but you certainly get the equivalent to cable errors, and I've been plagued by them on certain systems. It's revealing when you have a lot of systems with monitoring of ECC errors. I wouldn't like to say whether multiple DIMMs are necessarily more reliable even than rotating disks.

Memory in a regular desktop/laptop is basically the only part not protected by some kind of ECC algorithm.

If you care so much about data integrity, please start there.