@Robert_LeClair thank you for the info. Using AGOL looks generally viable, except it doesn't work with netcdf-based rasters. Anyhow, IMHO ESRI needs to put flashing neon warning signs on ArcGIS Pro telling users that it is not backward compatible. I've lost days of work because I assumed it was.... Now I need to re-create all my maps in ArcMap. Ugh...