I look at the rendering roadmap from time to time and noticed today that a different tab was added:
Can you tell us more about the Burst Occlusion Culling System!? As a dynamic culling solution, will it be enabled in Unity by default? How long do you guys think it will take to hit Unity? Will it be SRP-only? Will it replace Umbra or may Umbra still be a better solution for static scenes?
Most of all, I’m excited to see what you come up with!
I hope it will come to Default RP too
From a developer:
In the whole, the entire GPU work (BRG) unity is doing is looking really exciting, and it’s most likely to come to gameobjects as well. I haven’t seen/used it yet, but from what I’m hearing it’s a massive performance improvement.
HDRP will benefit greatly from this, and it really needs it to reach the scalability and get a performance boost to really push it to the next level. If it only comes to DOTS, I will literally lose my sanity 
DOTS is nice and all, but I really feel it depends on your project, for many you’re better off with the current system.
In other news,
if you’re looking for a really good static culling solution, check out “Perfect Culling” in the asset store.
It’s pixel perfect so very accurate, and it’s performance is insane.
There’s almost no overhead compared to umbra as your game gets bigger with more things to cull.
The problem with any custom or 3rd party culling solutions is that they always involve enabling and disabling renderers, because even in SRP culling is done inside Unity’s black box and is not “scriptable” and there’s no easy way to tell Unity which renderer is visible for which render pass.
For example, this makes it quite hard to cull an object that isn’t visible to the camera but would show up in a specific light’s shadow, it either draws on both or in none.
Unity needs to allow us to produce our own culling results to feed SRPs first.
It’s in progress on the roadmap now!!.. I hope that we get a considerable performance gains from it!!