[Kavelach]

Aside from what NateEag said, React is one thing, but the tooling is a completely different topic. When it comes to building your frontend, there was grunt and gulp (that I'm aware of), now the tools that get most love are I think webpack and esbuild. I didn't do anything with esbuild yet, but the way that applications are built changed a lot during the years, and webpack is much different that whatever there was before. Also, all of those tools are massive pains in your ass if something breaks, because debugging what actually broke is hard when your build process becomes more complicated.