Yeah it's kind of impossible to tell unless someone tells about it. I remember a Steemian in 2017 I believe mentioned he lost like 10-20k SP in a house fire. :/
Who knows with some of the old and big accounts, only time will tell. They'll be our Satoshi Nakamoto's. :D
I need to make sure my keys are everywhere. I will send them to you in a DM just in case ;D
Please don't, I don't want people hacking me thinking I have your keys saved on my PC. XD
:D