You don't need complexity until you do. Our company needed an internal tool, and they wanted remote access to it, but it was basically just a tool to generate

You don't need complexity until you do. Our company needed an internal tool, and they wanted remote access to it, but it was basically just a tool to generate a file based on a few inputs. We already had a command line program for it, so I wrapped it up in a web server and had it take input as a form input without any JS. It worked great for years, and then someone got tasked with updating it (mostly just combining it with other tools). He couldn't figure out how it worked, so he rewrote it to use a ton of JS, using Angular and other stuff. And guess what? He took longer to rewrite it than I spent the first time and made no functional changes besides some CSS and a ton of JS. With all these fancy new frameworks and browser features, it seems that many developers have forgotten (or never learned) how to do things simply. Frameworks and browser features have their place (I built an interactive HTML5 app as my first project at that company), but they're often completely unnecessary.