Your bundle.js file is 4.4MB and took 30 seconds to load (given several attempts). I would consider getting that under control, at the very least gzip the file.
Frameworks using frameworks using frameworks using frameworks.
Also: lots of front-end developers are into personal fame - and because they are front-end people they are also good at web-based marketing strategies. This works recursively :/
Oh and also: lots of front-end developers are relatively speaking weak in terms of architecture and general programming ability. (There; I said it.)
4MB is an incredible amount of Javascript. All of underscore is less than 6kb, jQuery is less than 70kb. Both of those libs fill out the "standard" library needs of most websites.
No excuse for 4mb though based on what the app does. 50k should do.
For example in a side project I tried SammyJs then realised it requires jQuery. So I just hunted for something that can route urls without the needless dependency. I chose Navigo.
Point is it takes some care but not too hard to keep the size reasonable. Also don't use npm for dependencies on a web site. But npm is ok for tooling e.g. webpack
The JavaScript is uncompressed and has 6
columns of comment characters on every line. There's really no excuse. This site did not even need JavaScript.