No not buying new, just using what was bought years ago. It still works, it does the job. Is it the best performance per watt, clearly no but the budget for electricity and the budget for new capital expenses are two different things.

If you go on Google cloud and select an E2 instance type (atleast in `us-central1` where my company runs most of it's infra) you'll usually get Broadwell chips.

replacing when and if energy, resources and effort required to run it surpass those required to replace it is efficient