Re-iterating on a similar question - If I do have the time and the cost to spend on writing e2e tests, do I still need unit or even integration tests?
Assuming it's a small application and writing e2e tests would not take us too much of time.
Note that E2E is the only level where I feel comfortable saying that. I don't think you could really consider yourself "safe" with any other level of the testing trophy alone.
Thank you Kent C. Dodds That is particularly the reason why I did not wanted to invest time into writing unit tests for my components as the overall functionality is already covered by the e2e tests. It makes me feel more confident about the overall functionality of my app.
I only feel the need of unit tests for certain utility functions and helper functions may be.