[gwbas1c]

But to add: Many of the "full stack" engineers on this site can probably write a clone of the early Craigslist or Facebook as a solo developer. They could even administer it through early growth. How many business are left that are that simple?

Back then, websites scaled more slowly, there were no mobile clients, and simple UI was fine. We could cut corners by mixing php, html, and SQL into a single file; but if you do that today you won't go much further than a hackathon.

Now you need a web site, API, mobile apps on both Android and iPhone, and maybe a desktop app. Tolerance of bugs is lower, so developers need to spend more time writing automated tests. The "web site" might be a mix of an in-house app, crm, blog, Facebook page, ect. No "full stack" developer can do all that in any reasonable time.