In Python you can simply subtract two rasters instead of using geoprocessing (raster calculator, subtract, minus)
subtract_result = raster_one - raster_two
Is there a way to do this with the ArcGIS Pro without using the SDK??
The SDK with geoprocessing being
var valueArray = Geoprocessing.MakeValueArray(rasterOne, rasterTwo);
var gpresult = await Geoprocessing.ExecuteToolAsync("Minus_sa", valueArray);