What happens when you run the following outside of ArcGIS:
import arcpy
import os
fld = r"C:\tmp"
desc_fld = arcpy.CreateFolder_management(fld, "describe")
arcpy.CreateFolder_management(desc_fld, "point_fc")
fgdb = arcpy.CreateFileGDB_management(desc_fld, "Default")
arcpy.CreateFeatureclass_management(fgdb, "point_fc", "POINT")
arcpy.CreateFeatureclass_management(fgdb, "line_fc", "POLYLINE")
arcpy.CreateFeatureclass_management(fgdb, "polygon_fc", "POLYGON")
arcpy.env.workspace = fgdb.getOutput(0)
for fc in arcpy.ListFeatureClasses("*"):
desc = arcpy.Describe(fc)
print "{} - {}".format(fc, desc.dataType)
The code above recreates the folder and GDB structure you display in the original post
and the results for me are:
point_fc - FeatureClass
line_fc - FeatureClass
polygon_fc - FeatureClass
>>>