How do you say "no"to high-paying customers demanding features that totally ruin your product focus?

Last week, a customer paying our highest tier threatened to churn unless we built a custom reporting dashboard that has nothing to do with our core workflow.

Saying no felt terrifying because of the MRR at stake. But saying yes would turn us into a bloated agency instead of a focused product.

for founders past the early stages: where do you draw the line between keeping enterprise revenue happy and protecting your product roadmap?