Or maybe they like to disconnect and talk about other stuff in their free time.

Does that matter if they do their work properly?

Yes, of course, because if you aren't talking about code 99% of your awake time, doing 54 projects in your free time, contributing to open-source libraries and writing blog posts and have no life or interested outside looking at a computer monitor you can't be a 1000000x engineer /s

Who needs to be a x10 engineer anyway - perhaps ppl need it to have a sense of self worth? I would only strive to get to x10 if I genuinely wanted to solve problems with those skills that require them. Like, working on my own projects and not having much time for them.

I certainly respect people who work hard to achieve expert status in any (worthwhile) domain.

Some people are just driven that way.

I have found passion rarly has much to do with talent in Tech. It's just a buzz word for, willing to be under paid and over worked becuase you have nothing better to do.

PS: When things are not going well, firing the energetic guy pulling 80 hour weeks may seem dumb. But sometimes it can make dramatic positive impact over time.