I think the desire to not centralize identity has more to do with it than anything. We present different facets to different communities. The pseudo-indelible nature of internet commentary means saying something to anyone potentially means saying it to everyone, in any context.
That's why people have multiple fediverse accounts, to limit context or purpose of communication channels. Not because they don't value genuine communication within those channels.
I think I somewhat agree with the author but I find the idea of a single account completely unappealing. My view on the benefits of federation is that you don't have a single entity gating your access. Having multiple accounts is a benefit.
I used to get into arguments with people in the Fedi who couldn't seem to make up their minds whether they wanted to be visible or invisible. To me it seemed like it made no sense, like if you really want to be invisible just don't post it because you can't really take things back.
At some point I realized those people were just like that.
I worked at a startup circa 2012 or so which was unusually unclear in its mission but the paychecks and the parties were good and the idea seemed to be helping people partition out different parts of the identities in terms of interests so you could get Paul-the-mild-mannered-applications-developer, Paul-as-a-marketer/huckster, and Paul-as-a-fox, and Paul-with-an-embarassing-interest, etc.
We had the hardest time explaining to the press (TechCrunch would say they didn't get it!) and everyone else, I could probably pitch it as well as anybody and I didn't do very well.