Hmm from your description, you sound very close to the author of that article. What makes you think they are extreme and you are not? Genuinely interested.
The end result may be similar, but the modus operandi is different.
The author frames the situation as "us vs. them". I don't do that. I have strong opinions too, but I don't act with despise or a hatred towards these entities.
I have seen the small web, and rise of web 2.0. So, it's just a progressive "I'll do this the old way" process for me.
What opened the floodgates for me was registering a domain. After getting it, I was able to put more and more of my life under it. My webpage, blog, other invisible infrastructure which improves my life started to move under it, yet I take a pragmatic approach. I'm a sysadmin and developer by trade, and I don't want a dozen more servers to manage, so I don't self-host everything myself, but use small/minimalist services which allows me to use my own domain.
Also, I'm not shy of sharing albums over Google Photos for example, because it's convenient for the recipients of the said albums. We're living in a social world, and I think balancing social aspects with personal choices is wise.
Because while I don't prefer bigger corporations, it doesn't give me the right to make other people's life harder. Life is already hard as it is.
I see it as expressing a feeling. "It feels like it's us vs them".
I don't know, I understand "extremist" as a pretty serious criticism ("I don't want to listen to that guy, he is an extremist"). But the author doesn't call for invading the Capitol, he is merely saying that he doesn't like how the commercial Web evolved.
Purism is an extreme position. Its extremism by setting it up as all or nothing, us vs them, or any other position that excludes the middle and only leaves the extreme positions.
I literally have no idea why invading capitols is topical for javascript in web pages, nor how such a comparison is relevant, so I can't comment on that.
I guess my point is that (the way I understand it) the author says that he feels like the web is splitting: on the one hand, those who are fine with the commercial web and ads, even if it means that they probably miss on some stuff that does not get the same marketing power. On the other hand, those who are not fine with it and run ad blockers and privacy tools, even if it means that they miss on some stuff that is only available through surveillance capitalism.
I don't know if we can say that a feeling (which is a descriptive concept) is "extremist". Then the author says that he feels like he is on the side of the ad blockers. Again, I don't see that as extremism. He is not saying "I will never open a commercial website in my life, and I strongly believe nobody should do it". He is saying "well if a commercial website works under my conditions, it's fine, but if they make sure to block me access because I don't want their ads, then I will live without their website".
