Your employer — and particularly your hiring manager when they become your line manager — is grateful for your time, I can assure you of that. You didn’t have to work there and a large part of accepting a role is wanting to work for / with someone.
It’s uncharitable to not bring at least some level of social pleasantry to the office every day.
I mean unless you work for Walmart or something. I assume we are both talking about senior, highly remunerated, creative and specialist technical work here, not breaking rocks.