Even the utility of too many tests is negative. More upkeep and harder to change the code.

And with LLMs also more context and token usage and cost.

The biggest differentiating factor today is engineers and/or decision maker willing to say no to a certain feature or implementation.

It's too easy to add bloat and complexity that can never go away, and with the tooling we now have a significant portion of engineers are now active risk to the projects they are working on.