Exporting a bundle for all platforms is very slow

It's still is unclear about which platforms can share asset bundles due to same format (and shaders?).

But regardless if you have to export a bundle to 4 different platforms and have a script to do that, it is very slow, as the editor re-imports all assets as it switches platform. This is very silly! Can it be made better?

Has 2019 introduced improvements?

 

2019.3, which is currently in beta, introduces AssetDatabase v2, which helps with that. Without that, you need to either use the Cache Server, or use different working directories for each platform. We do both of the latter options here.