Questions like this & this are either expecting simple Yes/No answer or a reference. References have been given to assert the statement or the proper citations have been provided yet the answer remained unaccepted.
I mean I don't find any reason for answers being not accepted in case of such questions? For questions with multiple possible answers diversified due to sects, opinions, etc. may not have any accepted answers. But the questions asking either Yes/No or relevant references ought to be accepted.