The number of tools has increased, but I think JS development has actually been simplified in some cases. This is largely due to the rise in popularity of rich clients talking to simple backend APIs. In older web projects JS always felt like an afterthought. Dependencies were managed totally by hand and your scripts were scattered throughout the backend templates. If you needed to do anything at all with your front-end code at build time, you had no choice but to glue some hacky solution onto the existing build process. Client and server were all mixed together, and it was painful.
Starting a project today, I can build a client in Javascript, hook it up to an API, and I'm done. NPM and Browserify make dependency management and builds a breeze. There's very little friction in the development workflow because the front-end build process it totally separate from the server. I make a change, save it, reload the page and I see my changes live without even running a server locally. Even PHP's deployment story isn't that simple.
It's true that the initial setup is more complicated than simply downloading jQuery and plopping it into an existing project, but if you have the option of separating your client and server code, it really simplifies things overall.