The market for talent is quite competitive. Companies need to pay market rates and have a staff that's large enough to compete. In a market where capital is cheap they will bid up rates and hire more people. If you don't do this you give your competitors a chance to beat you. Companies might be able to slow it down a little bit, but not entirely. Similarly in a market where capital is expensive they need to reduce the spend and team size.

Google is a public company. If part of the team is costing them more than the value they create for shareholders, there will be immense pressure to down size. This is actually healthy in a way since talent frees up for other companies. The bigger problem is that in the USA healthcare is tied to employment. That's messed up