"Servant leadership" is not a buzzword but it's been misused and abused by Big Corporations to the point that it basically lost its meaning [1].
For me - personally - the idea is about being less of a boss and more of a nightwatchman or janitor.
I believe in agency and ownership and - in sane environment - people can be left alone with clear objectives. It's more about removing obstacles.
I'll give you a simple example.
Once a week a maid comes to our apartment. Despite a clear power balance disproportion (it's easier to find a new maid than a senior engineer) and her being used to being transparent and prioritizing to not disturb tenants for me it's the other way around. I'm super happy to hastily finish a call or leave my room is she feels the need to disturb me, and if she needs an extra pair of hands I'm happy to help her with anything. After all, I'm more interested with the final result than feeling important.
We have a bucket list of tasks than has to be performed that slightly exceeds her capacity and she has a full right to prioritize things. It took my a while but I eventually convinced her that it's ok to skip things - like cleaning the windows - if she's feeling under the weather or it's cold outside rather than faking it.
Most of the pointy hairs I worked in corporate environments would probably prepare a list of requirements and walked through the apartment with a checklist every time she would finish giving her a full, harsh performance review.
But that doesn't build trust and long term relationship.
And after some time she developed - what people around here call ownership - and sometimes I feel she cares about the household more than I do.
Hope that makes sense.
I forgot where I read it (Steve McConnell?) but the best analogy I've heard for a boss/project leader is to think of your job is moving a house and the bosses job is to be a few streets ahead taking down telephone pole wires so you aren't slowed down.