The 2D case is kind of possible, see here. Though it is not exactly the most robust option, from my experience (probably due to floating point arithmetic).
In practice, the Convex Hull -node seems to silently ‘drop/loose’ input vertices, for large inputs (probably cocircular points).
I can recomend Open3d as a python-module to use for the task (assuming by “point cloud skinning”, you mean what is generally referred to as “surface reconstruction” in the literature).
For some usecases, you can create Points and missuse them as hacky data-container, including the possibility to use the Sort Elements -node.
But yes, handling arbitrary data in geometry nodes is currently ugly, hacky, hard to keep track of and cumbersome, at best.
We have the equivalent of user-defined functions (node-groups) but no equivalent to user-defined data-containers (e.g. lists, tuples), let alone datatypes (e.g. structs).
greetings, Kologe