Most folks are ambivalent about multi-dimensional support in GDAL, and they were ambivalent about subdatasets before that (which were a deficient implementation in a number of ways which precipitated the RFC). The RFC moved things forward in a positive direction, and it wasn't just about giving HDFLand a clean mapping to GDAL. It was about giving GDALLand the ability to more easily speak to an additional family of raster-like data. 

GDAL drivers that speak zarr, TileDB, Arrow, and HDF can now be adapted without the miserable compromises that subdatasets required in usability and data fidelity. That will allow people to bring the GDAL geo goodness to their data without reformatting simply to push it through the tool. I think these generic data structures are seeing much more action because they allow data-level interop without special purpose drivers across multiple software runtimes. The winds are blowing the same direction in point cloud land too.