Within the scope of an argument about the job mobility for Twitter engineers, Twitter is "just web dev stuff" or maybe "just planet-scale web dev stuff." The key point is that the skills these engineers have is valuable in many places and EM's behaviour is rapidly driving away everyone who has a reasonable chance of finding work within the next 6-12 months.
WHat I find interesting is the Twitter the business is no more "web stuff" than HN is "web stuff." The real business is on what we might call the product management side, and the central problem to solve when deciding what kind of social media product you have is deciding whether to moderate it, and if so, what you moderate and what you allow.
Even if he miraculously gets enough people motivated work there keeping the lights on and the machine humming, I am with the many people suggesting he has absolutely no idea how to actually run the product side of the business, where decisions like "anybody can rent a blue check for $8 a month" can have drastically negative consequences for the part of your business that sells advertising.
At this moment in time, that side of the business is extremely messy, and it isn't an engineering problem, it's a people problem.
Elon does not strike me as a people person, nor does he appear to be interested in delegating the most important role in the company—the person who decides what Twitter's product is—to anyone with competence in this area.
You are right that it isn't "just web dev", but at the same time the rest of the statement still holds. There's lots and lots of large-scale (mostly-)web services, and running one certainly isn't that groundbreaking anymore. If you really want to work on one, it doesn't have to be Twitter.
I imagine theres lots of groundbreaking stuff to work on at Twitter. Lots of opportunities to apply AI, do cool distributed systems research, build specialized hardware to optimize video, build new types of databases, apply computational social science (all things facebook does fyi). Its far far more than "just web dev". Now you can just stop working on your products and just hope the website stays alive but not sure its a good plan in the long run
Yeah they have problems that most companies don't, and a scale that most companies don't. But, web dev and scaling is not nearly as hard as car manufacturing or rocket design. Both of which are far more complex, also have a ton of software and people's lives are on the line.
put it on a shirt. twitter is the .01% of web dev. what they do isn't easy and there are no right answers.