Every time this sort of thing comes up, people piss and moan that password managers are too hard to use/etc. I've never used a password manager besides keychai

Every time this sort of thing comes up, people piss and moan that password managers are too hard to use/etc. I've never used a password manager besides keychain+safari (across several devices), and I just don't get the issues people claim to have. If third party password managers are so terrible why hasn't chrome/ff/etc got a better built in password manager? Or if they do, why don't people use them?