Hi,
Exactly the same issue with ArcGIS Pro 2.2!
In ArcGIS Pro, my point feature class has 47 points and only 2 points got an elevation from a SRTM1 Mosaic dataset. While in ArcGIS 10.5, all got an elevation from SRTM1 from the same Mosaic dataset.
Moreover, the Extract Values to Points tool in ArcGIS Pro 2.2 truncated my points shapefile! Any points falling outside the raster geographic extent were simply deleted from the output shapefile! Not a good behaviour.
For the time being, I don't have any option than reverting to ArcGIS 10.5 for this geoprocessing.
ESRI please fix this tool asap.