I think software development methodology 'erodes' over time.

For example original waterfall was kind of similar to agile methodology, there were re-estimations, milestones, prototyping... But I never heard anyone recently saying that our presumptions were wrong and we need to re-design and re-estimate.

Agile (scrum to be specific) in many companies is practically form of micromanagement. Number of companies are using 'agile' without automated tests and other necessary tools.