that little bit of work and attention is too much for most people.

I'm as frustrated about this as you are, but there is a large class of people who will not or can not understand and implement the password-manager workflow.

Of the people I know who are not in a tech career i'd say about 80% have nothing but contempt and ignorant fatalism toward security. The only success I've had is getting one older relative to start writing account credentials down in a little paper notebook and making sure there are numbers and letters in the passwords.