I think the problem is that people will never agree about the same definitions when discussing complex topics. For example, even when it comes to testing, I find that developers tend to disagree about definitions of 'Unit tests' vs 'Integration tests' vs 'End to end tests'. Some people will insist that a unit test should stub out all the dependencies and if you're testing a module and it invokes some internal sub-module (not mocked), they will insist that it's an integration test... Some people will say it's only an end-to-end test if it includes the front-end as well; other will say that if the test involves interaction with the database or other IO operations; then it can be called e2e.

There are a surprising number of topics; not only in engineering, but in day-to-day life as well, that we tend to think we all understand and have consensus about, but in reality nobody agrees on the same thing and there is no real consensus.

People tend to form consensus over labels; not over concepts. They may fully agree over labels but actually fundamentally disagree over the underlying concepts; they only realize this once they start defining their interpretation of the terms.