The default display mode of the hotspot is to be displayed according to the view (eg: rectilinear view).
It is very important that the hotspots to be distorted for immersive VR content that represent most of the cases.
The display mode that you need is something like this?https://threejs.org/examples/webgl_points_billboards.html
In this sample, all the point are facing the camera without distortion.
We have to think about how to implement this render mode in the HotspotD mechanics, can be useful for texts I guess?
Thanks for this feature request, have a nice day!