This is nothing new. I've heard that some well-known tech companies are offering fairly large additional stock-based long-term incentives (up to 2-3x salary in

This is nothing new. I've heard that some well-known tech companies are offering fairly large additional stock-based long-term incentives (up to 2-3x salary in some cases) to key senior engineering talent to keep teams together for the next few years. LTIs are a pretty standard retention practice in general, especially for key employees who are already at the top of their pay bands, but the churn in the industry over the last 18 months has probably driven up the actual value of them across the board, and potentially even shortened the vesting period.