Why does PointCloud not have a property ids?

[mxmws]

How can I assign IDs to my points? Am I missing something?

[EwingKang]

Points in a point cloud are in the form of core::tensor, which can be considered as vector/ array. The index to the itself is already a form of "ID".
What do you need that for? What's your use case?
You can consider using build a map between some kind of input source and the vector within the PointCloud structure.