I've seen the extremes of 100% tdd and 0 tests, and the most efficient projects/applications are the ones that are somewhere in the middle, you don't need tests for every single thing in your application and it becomes harmful to include them at a certain point.
My Personal preference is to focus on testing "critical" things like business logic, utilities,etc. Then have just a few end to end tests that skate the most important flows. In the end you have fairly tested application and you haven't wasted time asserting trivial pieces.
I've seen the extremes of 100% tdd and 0 tests, and the most efficient projects/applications are the ones that are somewhere in the middle, you don't need tests for every single thing in your application and it becomes harmful to include them at a certain point.
My Personal preference is to focus on testing "critical" things like business logic, utilities,etc. Then have just a few end to end tests that skate the most important flows. In the end you have fairly tested application and you haven't wasted time asserting trivial pieces.