I am saddened but not surprised at the lack of nuance in these comments. I also think the author is missing some things.
We take it for granted now that the public-ness of online content is very nearly binary: it's either public, and therefore hyper-public, globally accessible, indexed, searchable, publicly archived forever, or it is private. But this binary is artificial. Why can't we have things in-between?
Perhaps it's easier to understand if we make a real-world analogy. In the real world, there are public spaces where people interact and their interactions are, in general, not recorded, not remembered, not noticed. I can walk to my local public square and scream as much as I like about politics, and only people physically present there can hear me. If I say something strange enough, someone might film me and upload it to the internet, but that's an active choice. Almost everything that happens in these traditional public spaces does not have the hyper-publicity of web content. Likewise, I can have a casual conversation with a friend while walking in a public space, and people standing close to us might hear, they could even join in, but it's very unlikely that conversation will end up in the historical record. By contrast, while something like Twitter bills itself as a public square, it is nothing like it: no public square has cameras and microphones permanently fixed on it that globally broadcast everything happening there and pick up even the faintest voices. It really stretches the traditional conception of publicity. Previously, only celebrities and politicians had the misfortune of history's eyes being permanently fixed on them; what does “public figure” mean now?
Meanwhile, the web's conception of private is also an extreme. Conversations that nobody else can overhear and join are the only other option.
So, isn't publicly fetchable, but not indexable, content a reasonable compromise?
Now, certainly, the fact that there is no technical barrier to indexing means this is, you could say, privacy through obscurity. But that is true of almost all real-world privacy! It doesn't make it meaningless.
I also must reject the idea that because things can be indexed and archived, that they should be, especially when it goes against an explicitly expressed desire by affected users. Is mass surveillance only a problem when it is done in secret by a state?
The fact bad actors can't be stopped is a strange excuse as well. The world we live in is held together by the fact that most people, most of the time, act in good faith, even though they know a minority do not. If people gave up on caring because other people don't, there would be no society.
Finally: the legal aspect of the blog is such a strange attempt at proposing a solution. The fediverse is a system run by volunteers and its enemies (to be crude) are also generally volunteers, and the harms involved are generally at the micro, individual level (even if in aggregate they can be big), rather than having big corporate price tags attached. Licences are almost meaningless because almost nobody is taking anyone to court. The law cannot solve social problems like these.