I used to be of the mind that it’s my machine, and I’m going to log in as root because I don’t need to be hindered from doing what I want on my machine.
Over the years I gradually saw the wisdom of doing most things as a non root user, because it protects me from making dangerous mistakes, and it enables me to set up my system so I can share it with other people, and also there’s more and more software that complains that it doesn’t want to run as root.
But now I work at a job where I do a lot of things that involve being root a lot of the time. What you ask? Reading raw data from block devices mostly, updating system configuration that needs to change a lot. And I find typing sudo su plus my password all the time to be real annoying. The computer is supposed to be a tool for the human, not a tool to the human.
Also with the advent of virtual machines and containers there’s almost no need to ever share a machine with another person, you can always make them their own vm or container.
So I’m starting to lean back towards the logging-in-as-root side, because again, it really is my machine and I can do what I want with it, and having it stop me all the time so I can type “sudo su +password”, is annoying, since I’m just going to run the same command again anyway, and if it was a mistake, it’s just that much longer to make it happen before I can go fix my mistake.