IN which scenario would you switch to custom resource loader?

What title says.

In which scenario would you switch away from unity resource manager and use custom/manual resource loader? Think about loading things from streamingassets by code.

 

If I had a project with a large number of assets which need to be dynamically loaded/unloaded during gameplay I'd appreciate a ready made manager facilitating that.

 

Pretty much anything where you have things that update on the client that you want to persist. Or where you have custom formats and going through assets offers no value and is just an additional performance hit.

With DOTS the use cases go up dramatically. Because since everything is data in the form of structs, you can just save/load the raw data via unsafe pointers. No serialization or any processing just stream data on disk directly into memory. DOTS sub scenes do that and more and more people are using the same core approach for all sorts of things.