You can’t just “turn on” ray tracing and expect good performance. It’s a very complex and GPU heavy rendering method that requires careful optimization on a per object, material light basis. I’m successfully using raytracing in some quite heavy scenes, after optimizing how and for what it is used for. For example, it can actually be more efficient to use ray traced reflections for very glossy surfaces than planar reflections, while using it on surfaces with some roughness will quickly drop frame rates to single digits. In my opinion,  global illumination isn’t worth it in most cases. Baked lighting will perform and look much better. 

This isn’t really an Aximmetry issue, so you can use the general Epic UE4 tutorials and documentation on the subject to better understand how everything fits together.

You should actually read through all the Unreal Engine documentation on it. If plan your projects correctly and build models and everything in your scene with the underlying technology in mind you wont face these issues. This is not an Aximmetry issue or an Unreal Engine issue. This is a you haven't taken the time to deeply understand the technology issue. I run a very complex scene with full global illumination, static lighting completely disabled with ray tracing an what is now worse then your GPU based on time period. I run a 4070Ti SUPER. You were running one tier above me. Let me be clear, i did just pop things in the scene and have it work. At first i was getting about 10 FPS but you optimize as you go. Now I run smooth at 60FPS which is double what I need. It can be done but you need to take the time to understand the tech. There is a reason large studios can put out games that are massive with global illumination and they run on an XBox. Trust me its not Aximmetry or Unreal. 

The good news is that if you take the time to learn the tech can empower you to create some pretty amazing things.