I agree with this take by Jacob Kaplan-Moss that you should be able to estimate very accurately and then just not do it most of the time. Learning how to estimate is a non-negotiable part of building an intuition for software engineering. It’s not the estimation that we need, it’s the intuition.
The other reason why we wouldn’t do it all the time is because estimation (AND tracking, oftentimes people estimate without a tracking mechanism) has a real cost attached to it both to the team doing the estimations and to the org as a whole. Relying on estimations makes the entire organization less agile.
The follow-up post has a bunch of ways how you can estimate better but it doesn’t reference my preferred one: critical chain