Did a little digging, apparently in a 2021 lawsuit, documents were released with bad redactions (they blacked out over the data, but the underlying information was still able to be highlighted and copied/pasted. Very common error when redacting PDFs)
I haven’t checked the data myself but according one user this was the breakdown:
“Total staff as of 2021: 336 people
Administration: 35 people making an average of 4.5 million a year
Game Developers: 181 people making an average of 1 million a year
Steam Developers: 79 people making an average of 960k a year
Hardware Developers: 41 people making average of 430k a year”
Normally I would guess that “average” here probably means a few people making a ton of money while others get shafted. But I think “admin” probably accounts for that. We have no official way of knowing the true breakdown since this info is not supposed to be public