I never heard of "waterfall" until it was from detractors who were fanatic about agile and TDD. I think it's likely a myth, like that one that everyone recites with the same hollow-eyed conviction, that we all wrote unnecessary code or that we never did any testing.
All this is bullshit.
Of course we talked to each other. Dear god how could we get anything done if we didn't coordinate? Do you really believe we worked like that?
Sometimes we had bona fide meetings of a subset of a group, just the ones working together on a feature; more often we stood in each others' doorways and had brief talks. It was not at all ceremonial like these sprint things. I usually had a tester I worked with and spent a lot of time in his office; he'd find a bug, I would fix it, he'd retest, and it would not go into any bug-tracking system for managers to hold against me if they decided they didn't like my face; in fact it went online within the hour. Talk about pressure.
But we didn't have anything as stupid as a daily standup that required us to drive in rush hour traffic and start the day pissed off and weary. We did status updates in email and we were requested to have them in by 11:00 or so.
I did agile at the last place I worked in the USA. I found it supremely ridiculous, like people playing chess out of a book of classic games instead of making their own moves. Nobody was dependent on my work, I was dependent on nobody else's. But I had to sit there struggling to stay awake, struggling to hold my temper.
From what I can tell my career has been a lot more solo than most people's. Of course I've worked in groups (calling them "teams" is recent and I don't like it) but usually I own large components and when I do coordinate with others it's at a very high level of division, like I do the servers/database, and someone else does the browser. Before I had finished my third year as a developer I had shipped two Microsoft products singlehandedly in the new SQL Server group. It seems now like most people have never enjoyed that kind of independence and regard people like me as stealing responsibility from others. My desire to work uninterrupted is seen as effete and "toxic." Anyway I am starting to repeat the article you read, so I'll shuddup.