This 100% this. I run my teams via "Kanban" (I don't know how kanban it actually is, but that's what I call it).

The only question I ask around prioritization is "Is it worth doing?" If the answer is yes, I ask the stakeholder if they care how long it takes. If they do, I ask for a range and give a best estimate if it's achievable. If the answer is no, I ask why they care how long it takes if it's the most important thing to do.

My engineers know that they're expected to do that one project to completion, and we loop in other stakeholders (marketing, sales, QA, etc) progressively as we approach completion. Admittedly I work at a company of 20, but it works remarkably well, despite the absence of a "schedule"