There seems to be an incongruity between `geometry` and `.t.geometry` APIs for PointClouds.

[rtviii]

Checklist

• [X] I have searched for similar issues.
• [X] For Python issues, I have tested with the latest development wheel.
• [X] I have checked the release documentation and the latest documentation (for main branch).

My Question

I found it extremely unituitive that you can create .t.geometry PointClouds with labels but can't save them via the regular io. Is there a way to do this?