Oh wow interesting 🤔!

Thank you for the compliments and no problem :)! Looking forward to see what you do with it :D

The hair curves can use GN, but currently that is only for generating the hair curves and not for simulating them (unless you create your own solver, which is a very complex task).

I made a video on how to use the old hair dynamics for the simulation. It is simpler that way.
youtu.be/Ds9uW7t0oLI

The "new" hair curves don't have official simulation yet (It is in active development though)

You can create your own solver with geometry nodes

or

You can also convert the hair curves into the old hair particle system which does have hair physics but the simulator isn't the most stable.

Maybe try Armor Paint but it is in alpha stage (and has been for a while)

Alembic I/O improvements regarding custom attributes on curves/edges and points.

Haven't tested it in a while but as far as I know only attributes on surfaces work but not on geometry with no faces.