If you can't make firm delivery commitments to customers then they'll find someone who can. Losing customers, or not signing them in the first place, is the most harmful thing to everyone in the organization. Some engineers are oddly reluctant to accept that reality.
Estimating the delivery of a product whose absence means zero product for the customer is very different. A company that’s already humming along can be slow on a feature and customers wouldn’t even know. A company that’s not already humming is still trying to persuade customers that they deserve to not die.
Rather: the customer will find someone who can confidently pretend that thet can make firm delivery commitments.