He doesn't say why a library interface would be better. That's why I'm saying he doesn't even address the main point of LSPs, which is that they came in response to have your IDE or editor maybe-kind of plug into some libraries and wish for the best. Just saying that a library interface would be better because it's less complex is meaningless, when we obviously have not managed to get anything close to that for the past 40 years.
It's not super convincing to just dismiss the only solution that seems to have sort of worked by saying that we only had to keep doing it the way that never really worked.
I'm sure the implementation can be a lot better, but he does not provide any argument for why the architecture itself is bad. Sometimes abstractions are actually useful.
I also think it's a bit overblown to call communication with a locally running process a "distributed system". I mean, that's kind of true, but not really any more true than if you were to call having multiple threads in your process a "distributed system".
It introduces _some_ of the failure modes of a distributed system, like unsynchronized / inconsistent data, but not all, like network failures. I think he does have a point there -- as a user, I should not have to care whether an IDE talks to a library via its API or to a language server via LSP, but here I am, watching WebStorm to act up and complain that the TS language server crashed.
One thing that Blow misses IMHO is to what extent libraries introduce these failure modes _too_: A library can crash as well (and take down the IDE with it), and multiple libraries that deal with the same data can get inconsistent. That's actually a problem of quality control, integrating code from multiple third parties, and so on.
Security, too. If I’m editing a .env file with a bunch of passwords in one buffer, or maybe some sensitive data I copied and pasted into an empty text window I’m using for temporary notes, I don’t necessarily want some random code written by some 3rd party running in the same process space. I mean, most of userland is pretty much written by various random people already, but I might trust a language server to tell me that I forgot a semicolon in a shell script without trusting it with the contents of /etc/shadow.
It's not super convincing to just dismiss the only solution that seems to have sort of worked by saying that we only had to keep doing it the way that never really worked.
I'm sure the implementation can be a lot better, but he does not provide any argument for why the architecture itself is bad. Sometimes abstractions are actually useful.