Yes, but if you are leaning on your test suite to verify a huge refactor, you are unlikely to make the kind of sweeping design changes that are sometimes needed.

For example, say your ORM is causing major trouble and you need to replace everything from the controller back to the database. Heck, maybe you decouple the whole backend out into an API. The only tests that help you are the end to end tests. The rest of your test suite for your backend needs to be thrown away as much as your backend itself does.