yeah technologically the stack gets a lot more complicated. but for users and companies managing/selling it, it's a lot simpler. you don't have to update the software, it's in the cloud, so there's no security holes that go unpatched. your docs are backed up so hard drive or power failure isn't a problem. you don't have to move files. it's insanely easy to share docs.
besides, there are a lot more boxes sitting on top of each other in this stack but it's not any more difficult for a developer. in fact, it might be simpler. the extra layers offer some abstractions. instead of having to know native windowing on 3 different systems, your just write a compliant webapp in a nice, high-level language with all sorts of toolkits that do 90% of the crap anyway.
Right, I see the browser as a hard wall, while it needs to know all the native implementations, the stack above it does not. So it is technically more complex if one person where to master it all, but for two distinct roles it is far simpler.
I will admit that I did not see the vision in 05 but by 08 I was on-board. When I figured out that JavaScript could be used to entirely replace server pages is when it dawned on me. Before that I just thought AJAX was sprinkled onto server pages and I thought great we are adding even more to the stack. But when someone showed me how to write apps with JavaScript to control all aspects of the view, and call REST services, I was sold. It cleanly separates the separate concerns of web app development, which up until that point was a soup of HTML/CSS/JavaScript/(JSP||ASP||PHP)/ and back end code. Many times web developers would inherit projects that had all of those in a single file. We like to preach discipline but I have inherited more that have had none than that do. So for me the new way of developing web apps is a god send due to the fact that the back end and the front end are now wholly separated. Even if the front end technologies get muddled together it is far simpler to fix than extracting UI logic from business logic. So to me, the new stack from a web app developers perspective is far simpler and enforces better architectural discipline.
besides, there are a lot more boxes sitting on top of each other in this stack but it's not any more difficult for a developer. in fact, it might be simpler. the extra layers offer some abstractions. instead of having to know native windowing on 3 different systems, your just write a compliant webapp in a nice, high-level language with all sorts of toolkits that do 90% of the crap anyway.