like I said... not noticeable speed difference... unless people sip coffee faster than I do
Plus the dictionary is easier to work with
d = arcpy.da.Describe(in_fc2)
d.keys()
Out[20]: dict_keys(['datasetType', 'children', 'hasM', 'FIDSet', 'extent',
'metadataRetrieved', 'name', 'hasGlobalID', 'dataElementType', 'isVersioned',
'representations', 'catalogPath', 'modelName', 'isCOGOEnabled', 'editorFieldName',
'areaFieldName', 'createdAtFieldName', 'changeTracked', 'extensionProperties',
'ZExtent', 'featureType', 'fields', 'fullPropsRetrieved', 'OIDFieldName', 'file',
'creatorFieldName', 'versionedView', 'indexes', 'childrenExpanded', 'rasterFieldName',
'canVersion', 'geometryStorage', 'relationshipClassNames', 'lengthFieldName',
'defaultSubtypeCode', 'hasZ', 'shapeFieldName', 'shapeType', 'aliasName', 'dataType',
'baseName', 'DSID', 'globalIDFieldName', 'extension', 'hasOID', 'MExtent', 'path',
'isTimeInUTC', 'spatialReference', 'editorTrackingEnabled', 'editedAtFieldName',
'subtypeFieldName', 'hasSpatialIndex'])
And timing results are variable, depending on what you are timing and how
import arcpy
%timeit(arcpy.Describe(in_fc2))
97.6 ms ± 4.61 ms per loop (mean ± std. dev. of 7 runs, 10 loops each)
%timeit(arcpy.da.Describe(in_fc2))
249 ms ± 3.35 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)