There is a very unorthodox opinion expressed by James O Coplien, Agile Coach, that most unit tests are waste.
I would agree with some of the points he made in the article. Too many unit tests are wasteful. Especially if they do not reflect business logic. However, I still think there is a value in unit tests as soon as they represent functional specification to the code being written.
I believe there are certain situations where your best bet is unit test. It allows you to cover some sophisticated logic and it is beneficial to write code since people tend to find bugs in their code while developing code.
That said, I firmly believe that caring for most of business-related functionality must be delegated to bots since humans just can’t keep up with the code being written and can’t cover the amount of functionality which can be covered by systems like testRigor.