As the article's author pointed out, you don't need many of those addons in UE4 because the functionality is ALREADY built into the engine.
Want realistic car physics? Already built in! Want great shaders? Already built in! Want rigged faces or a cityscape background? As regular assets, buy them anywhere on the internet (including the Unity asset store), and then put them into UE4!
And this is why one of Unity's strengths is also one of its weaknesses. The reliance on so many third party libraries for basic functionality means that A) integration with the engine isn't always perfect, B) updates and fixes are dependent on the third party author, and C) the UT community is nickeled and dimed for many things which should be included already.