I had a repair person look at the fridge about a week after purchase and they identified two different noises, one which they said was normal and coming from the compressor (ie the noise I found annoying), and one which they thought was being caused by whatever part is attached to the compressor that turns it on and off. They briefly unplugged the fridge and plugged it back in, stating this should help with that second noise.
I was disappointed by the news, but agreed to let them order the part since they seemed to think there was something off about it. That was scheduled to be installed about four weeks after my purchase.
In the meantime, the fridge just randomly got quieter one day out of the blue and has stayed quieter ever since. No idea why.
The repair person switched out that one part, which came with insulation wrapped around it, and that was that. I don't think it had anything to do with the fridge getting quieter, though, since that happened between the two visits.
I still hear it running if I'm right near it, but not at the level I did before, and I'm no longer hyper aware of it.
So my point is, if it's new, try unplugging it and plugging it back in (the tech said sometimes it helps) and also give it a bit of time. Hopefully it will "calm down" after a few weeks.