IMO building classic websites is a solved problem, while building web apps isn't. Classic websites have CMS, things like Wordpress, and a ton of MVC frameworks

IMO building classic websites is a solved problem, while building web apps isn't. Classic websites have CMS, things like Wordpress, and a ton of MVC frameworks that have been tweaked over the last decade, like Rails, Django, ASP.NET MVC, etc. When it wasn't a solved problem, a new one like this was popping up in the news every other week. Now, that that's done, people are trying to do other things, like complex web apps...and so that's where the brain time is being spent.