I didn’t say the source of failure. I said a source of ambiguity. And having also been in the industry for decades, I have encountered it many times, where a junior programmer or somebody new to a project read some documentation and assumed a behavior which in fact did not match the current implementation. So you may have been fortunate, but your experience is certainly not ubiquitous.

With respect to variable names, I’d suggest those too should absolutely be updated too if the name is given in a way that adds ambiguity.

I’m not saying comments are bad; rather that bad comments are bad, and sometimes worse than no comment.