Downsizing via attrition means your losses are focused on those with both desire and ability to work elsewhere, and so you keep those who can’t or don’t want to.

“Don’t want to leave” is good, “can’t get hired anywhere else” is bad, and the presence of the latter makes it more desirable to leave even places which used to be fun.

That’s another way of saying incompetence.

If you want to roll the dice on a new employee then fire the old one. This kind of 10% cut results in losing your best who don’t wait around and just start looking on day one. Worse, they often leave after your round of cuts as getting an offer is outside of your timeframe.

What's the current SpaceX attrition rate like, and how does that change across different organizations? It could be a response to their attempt to gain additional funding, and something they heard or agreed to for said funding. Speculation, but wouldn't surprise me.

SpaceX does not make that public. Best number I saw was 50% of new employees made it to 18 months suggesting rather high annual turnover. Long hours + low pay really add up.