Bloat is real, but there's another labor market dynamic in play here.
There was a huge run-up in corporate employee compensation in the tech sector over the last few years. (Some called it a "shortage," remember. Some of it is genuine growth in the sector, some of it was definitely "labor hoarding" by large companies that could afford to carry excess staff in a tight market as a hedge against being unable to fill critical roles - or to deny talent to competitors.)
While I would be surprised to learn of explicit collusion to suppress wages (unlike the _In re: High-Tech Employee Antitrust Litigation_ case,) collusion is not needed. The more tech employers lay people off, the more incentive there is for the next large tech employer to announce a layoff, and that's discoverable without collusion. In the aggregate, the benefit to flooding the market to reduce employee bargaining power offsets potential loss of critical talent, because it drives down the cost of acquiring new talent.
The "war for talent" quickly turns to the "war on talent."