The problem with E2E tests is that if a problem is discovered, who will fix it? It's okay if you have small teams that look after UI or the back end. Someone has to triage the test failure and determine if it is a UI or back-end issue. But when you have larger full-stack teams that own different parts of the UI and backend, you can't afford to spend too much time on triaging bugs. You need to be able to determine and get the feedback of a failure quickly, such as with an Integration Test or even a component test. There need to be E2E tests for things such as critical customer journeys, or authentication flows in the app. But really E2E testing isn't 100% needed.