.@theluthier on the stream you mentioned that you tried reflection probes and didn’t like it. Here I have an example of why and when should you use it.
Here is an example of what you get with just SSR enabled. Since it’s screen space reflections it doesn’t count in anything that is beyond the screen space. You can see this cylinder is just partially reflected in the sphere. 
And here is another example. I added a cubemap reflection probe and irradiance volume. Then I hit “Bake Indirect Lighting”, but for this example, you could just hit “Bake Cubemap Only”. How I see what it does is Reflection Probe capture everything that is added into it’s “Visibility Collection” (to exclude sphere itself, for example) to a cubemap texture and Irradiance volume is using this information to put reflections where it should be. So even while the cylinder is now off a screen space a bit, it still reflects as it should be.
Maybe the lighting is not best quality this time, but I’ll try to get deeper this week.
PS: I believe you should not bake dynamic objects into cubemap, if you are doing animation.