I feel like the core problem here is one that can never be resolved, because it's the result of two valid but opposing forces.
On one hand you have business stakeholders, who can see the business reality - money doesn't grow on trees and runways are very real and scary, so without deadlines companies fundamentally cannot function.
On the other hand you have engineers, who either explicitly or implicitly understand the other truth - that reliably estimating a project requires knowing all the steps involved, and if you know all the steps involved, then you'd have already automated it.
On one hand you have business stakeholders, who can see the business reality - money doesn't grow on trees and runways are very real and scary, so without deadlines companies fundamentally cannot function.
On the other hand you have engineers, who either explicitly or implicitly understand the other truth - that reliably estimating a project requires knowing all the steps involved, and if you know all the steps involved, then you'd have already automated it.