Its like 2 weeks since I had to grasp react, fluentui, react hook forms, webpack and a little more when I started using modules and even more when I used typescript.
React clicked really fast, documentation new and old, articles helped get on track really fast.
Wiring that all together and taming CRA (Create-react-app) with react-app-rewired to add stuff to webpack, like adding libraries to behave like modules that are NOT modules, packing all with scripts into single html, understanding where are boundaries between fluentui and react (both new to me), setting up monorepo because I separate reusable components from app itself and libs, applying css which I am bad at and stuff like that took more time... complexity just explodes, but less "mental effort" overall achieved by having streamlined build, reusable stuff etc.
Otherwise I feel that building app with react takes a lot of "mental effort" away, because you develop a component in isolation which feels simple and when you use that component you don't think about implementation details - it is nicely abstracted away and things just work.
Ah, yes, and I'm lucky I got the signal that functional components are way to go and the only place I had to use a small class component when I want to have a component variant for existing class based component from FluentUi where generic types are important and used within `onRenderItem` and various methods:
> class LookupBaseInternal extends BasePicker<ILookupResultProps, ILookupPropsInternal> {}