The regridding bullet point was an attempt to nerd-snipe someone(s) into fleshing out the prototype that Ryan showed is possible (here Conservative Region Aggregation with Xarray, Geopandas and Sparse).
@keewis also said
(I have something like this working in https://github.com/IAOCEA/xarray-healpy, where the name is not that descriptive… it really is just general regridding using a tree and numba to do bilinear interpolation)
IMO this would be a great project for an institution to take ownership of - it requires sustained effort to flesh out, but would certainly be extremely widely used. But anyone interested in that should probably go to the thread linked above.