If you're going to be writing a lot of CSS, then using SASS might save you some time and improve readability. If you're writing a webapp, then a SPA or React app might be the best course. And if it's image heavy, then a tool to automatically compress images would likely make sense.

If this is too complicated to manage, then other tools like task runners or Webpack can help automate the process. Node packaging can be used to sync settings across all project owners.

Taken on their own, it seems like a lot of complexity. But if you're only adding tools when you need them, it's really not that bad.

I wrote my last site in Jekyll + SASS. No Webpack, no gulp, no React. I just didn't need them, so I avoided the complication.

I'm glad they're there if I decide I want them, though.

Some people would consider it a bad thing that eg. Backbone hasnt had a major version in years but it is still perfectly capable for many use cases and it performs well. Of course you have to have more experience and knowledge with JS and frontend development in general to get these results I think.