In the years since, the incentives to leave one's current employer have decreased. Salaries have stagnated, there's been belt tightening and layoffs, the pool of applicants competing for the same jobs has become bigger, and a lot of folks who've gotten cushy benefits like permanent WFH arrangements would have to go back to the office if they changed jobs.
But that means that a lot of tech companies are experiencing lower than normal attrition, but there's still professional growth happening, and the only way the companies have been able to reward employees is through promotions. That has led to bloat at the management layer, which this year many companies have tried to address, either by letting managers go or sending them back into IC roles.
I predict that due to "tenure lock" (where a lot of people who moved in the Great Migration have the same tenure at their current company) we're likely to hit a watershed moment that leads to another Great Migration later in the decade.