These sorts of massive cuts, coupled with massively decreasing workplace quality, and with removing any chance of financial reward (no more liquidity in shares of the company!!), are going to cause the most talented people to go to greener pastures.

The people who stay will be those with the least options.

Musk has made employment at Twitter hugely risky, with no possibility of reward. Really boneheaded business, completely incompetent cutting off the workforce, honestly. Hard to imagine a worse way of pruning the workforce.