The voxel plugin on the marketplace currently provides features such as destroying landscapes and digging holes or caves during design and play. For me this is a real world feature being able to design a cave system by tunneling through a mountain. I don’t know if voxels are the only way to achieve this but I think being able to destroy a landscape is something that should be built into the engine.
100% agree on that. Look at the cave in unreal5 video, looks like that kind of made cave. but having it eat away at it would be nice.
Currently, yes.
What unreal calls a “landscape” is a sorry excuse for a “landscape” to begin with, BUT… What you are asking is not a feature of any landscape, it’s a game play function vital to your game that you as the developer should develop.
You can think of voxels as cubes that can be removed or added in at runtime.
You can think of a landscape as a flat sheet who’s vertex can be moved up or down (not at runtime usually because that wouldn’t affect collision the way it’s currently built)
In the case of boxes it’s pretty easy to say “go away” and make the collision work at runtime.
In the case of the flat sheet, a change would cause a need for re-computation of the whole sheet.
TL:DR;
Voxels may not be the only way to achieve what you need, but they are likely the smartest way currently available.
PS: They should already, but make sure whatever plugin you purchase uses Octree or look up what better math may be available today (kd-tree Could be better with the newer GFX? this is probably an opinion driven debate. google 
)
Thanks for the response. Actually part of what I am talking about is a landscape design feature not just a gameplay feature. See this video for an example of what I am talking about. Brushify - Caves in UE4 using Voxel Plugin - YouTube
That’s not a “landscape feature”.
It is a nice feature that negatively impacts performance for 0 to no gain.
When doing things properly, Game Level Design is done in a 3d app by creating specific - and possibly modular - pieces of geometry.
This is true for anything at a professional level that isn’t made by someone just having fun. When you are having fun, then performance doesn’t matter. you can do whatever.