Continuous integration and demos to stakeholders (devs, designers, product managers etc) every 2 weeks - these practices are now engrained :-) It's frequent to then do corrections after these demos, and that really helps ensuring the product manager is getting what their customers need.

Easy to forget waterfall in 1970s / 80s really meant teams working on their own for months and then realizing there is no way to assemble the whole product from the parts. Or that the industry has moved on and the product is obsolete.

Agile as "devs can do what they want" never really existed ;-) Managers always have to plan / T-Shirt size resources (time, devs) to some degree. For stuff that's really hard to break into tasks, the magic word is "the plan is to do a POC first".

Coming from someone who also doesn't like teams being asked to break their unknowns into 30 known tasks. It's a compromise... I agree with all your points on how Agile is abused / misunderstood. Yet i believe in the progress from continuous integration and regular demos to stakeholders as a sign we did change something....