Jblow's entire schtick seems to be "everything is wrong and nobody is good at anything" which is a very easy position to hold because it doesn't require you to do anything successful/productive to express it (as opposed to: I have here, in my hand, the solution to all this mess that I built myself - much harder) and also tends to trick stupider people into thinking it is deep and perceptive.
it does, at times, yield interesting criticisms. The criticism is valid. The criticism is also easy. Everybody knows there are issues here and there and most people (including people who seem to tolerate them just fine and live normal lives - aka the "stupid" people) can easily point out a handful. It doesn't make someone smarter or better to refuse to write javascript and make videos online about how modern software development is bogus. You're not fooling anyone.
Thing is this stuff is still fun to watch because it does feel like you are in on some big secret that nobody else knows (even though everybody else already knows - they just don't care) - and in that way, it is actually as much of a "brain rot" as social media or TV or whatever (all of which he also has videos on).
In short: Judge people not by the issues they raise but by the solutions they bring to those issues. Jonathan Blow's seems to be writing a new programming language - which I consider to be completely retarted. I think the bottom line is that the point is completely missed with all this modern software whining: The rest of us recognize that, despite its various issues, it does help us solve problems faster or more effectively, and as a result we are not writing new programming languages. We are more effective at getting things done because we are able to use modern tools without throwing a temper tantrum about their inefficiencies or abstractions or the fact that they allow us to learn javascript without learning assembly or something.
Anywho Jblow's software critique should be considered hand-in-hand with his lifetime software output: Braid, The Witness, and a series of vaguely cantankerous youtube videos. He had the good fortune of being born into a time in computing that allowed him to watch the growth of modern software development and now has the perspective/distance required to critique it. We will see, in the long run, if any of us modern idiots are able to out-produce his lifetime output with the benefit of our flawed and inefficient modern toolset.