Most average people are not sure of password managers because the idea of losing the god password and losing access to EVERYTHING is terrifying, and there is mathematically no way to recover your secrets. Most normal people have lost a password before, so that's something they think about.
Also for most normal people, an unencrypted note on their desktop with plaintext passwords that are DIFFERENT FOR EVERY SITE is STILL more secure than the SOP of using one strong password for everything. For that to be compromised, someone needs to be able to run code on my local machine, in which case, they can just install a keylogger, so encrypted passwords are no increase in security. I genuinely don't care if App1 on my computer can fiddle with App2's bits, because I chose to run App1 and App2, they are trusted.
Also for most normal people, an unencrypted note on their desktop with plaintext passwords that are DIFFERENT FOR EVERY SITE is STILL more secure than the SOP of using one strong password for everything. For that to be compromised, someone needs to be able to run code on my local machine, in which case, they can just install a keylogger, so encrypted passwords are no increase in security. I genuinely don't care if App1 on my computer can fiddle with App2's bits, because I chose to run App1 and App2, they are trusted.