Do you see increasing file size for the VDBs exported in higher resolutions? If yes, and you don't see any detail added in Blender, do you have a parameter called 'step size' somewhere in Blender's VDB object/shader or render settings? Maybe it's set too high, in that case any detail lower than that value will not be visible.
The cloud detail in TG is derived form the noise function, while the exported VDB is the voxel cache used for lighting/GI.
Divide the cloud extents in meters by the voxel cache count in any axis, that's what the real voxel resolution is. For massive clouds it can still be 10, 20 meters per voxel, and that's much less detail than TG uses internally for rendering.
As for rendering clouds - same here, I saw some recent renders from Blender with cloud VDBs simulated in Houdini - both the render and clouds were beautiful, the best I've ever seen to date, absolutely stunning results. TG struggles with some non-physical behavior while all the path tracers have a clear advantage here. TG's results might be 'artistic' and good looking most of the time but it takes quite some time to get good realistic results... and they still lack the shading quality and detail of other renderers' results.
I wonder what the strategy is now that clouds simulated in Embergen or Houdini are much more advanced and realistic than anything you could get in TG after days of tweaking. Also, the inability to import VDBs in TG and the noise-based random clouds heavily limit artistic freedom. TG's advantage is a relatively care-free realistic atmosphere but cloud shading is quite lacking to be honest if realism is the goal. TG's restrictive EULA when it comes to selling VDB cloud assets generated in it might not be helpful, too.
BTW, that cloud looks great!
