How can one build a community without video and livestreaming in 2021? Not that I like it but even hard-core tech communities, eg in the embedded space, have some video exposure. Or big discords have often some video/streaming outlet.
Multiplayer game communities - not the watchers but the players - are also one.
I enjoyed the article but realized reading it there are different types of community. The form discussed there is more business/promotional, which is different from HN or MMOs.
b) Video/Streaming is not for everyone. I prefer my technical discussions in text, with a few well chosen illustrations. There's nothing that makes my heart sink more than hearing "well, if you just watch this rambling, 2 hour stream of consciousness explanation, it will all become clear to you" (Worst of all, there are companies now doing this in lieu of manuals).