Estimates are difficult for developers and product owners

This is why I push for Kanban whenever I am a PO. If we can ballpark an estimate, I can prioritize it. If we cannot ballpark an estimate, I can prioritize the research to clear out some of the unknowns. But most importantly, we set an expectation of rolling feature rollouts, not inflexible release dates. We communicate both internally and externally the next few things we are working on, but no hard dates. The article correctly identifies that hard release dates communicated to customers are the root cause of problems, so I simply don't give such things out.