There's a lot of incentive. The problem is HR and employers have decided to turn a blind eye to it in favor of looking at the next quarter.

Why give someone a 10% raise because the market has spoken when you might be able to retain them with a 5% raise? Even if you hire new employees at a premium, some contingent of older employees will stick around just because switching jobs is a hassle. This sort of thing drives down quarterly costs which ultimately makes you look good to shareholders who can't see the internal destruction.

Reducing attrition is a good incentive, especially these days. Whether it's enough is another question.

Do companies care? Their solution seems to be to hire more recruiters.

My wife is a tech recruiter, my bread gets buttered on both sides. It's a really funny market.