Multiple rules are available for authors to do citation for the sources used by them in their research. Researchers carry their own individual strong beliefs in context to which convention is best suited for citation. Larger professional organisations issue lengthy guidelines in this context. Among the most widely accepted and adopted guidelines are of the American Psychological Association (APA), Modern Language Association (MLA) and The University of Chicago Press. Other than this, some research journals follow their own system.
The question here is, is one better than the other? Well, they are all fine and all of them are merely conventions. It would be a futile attempt to compare these widely accepted conventions as one would not be able to come to any conclusion. Like a discussion which side of the road is better to drive cannot conclude on a decisive note, neither can this.
There is one criterion that has to be adopted for citation. All that is essentially required is that the readers should be able to check for sources of accuracy. As long as this is taken care of, the system is good.
People have their own set of preferences. Usually, the generalised response is not in favour of in text citation system. Researchers and readers usually opt for and approve of footnotes and endnotes for citation. The common concern in this case is that in text citation is annoying and came in the way making the content appear cluttered and confusing. Irrespective of this drawback if in text citation, The APA uses in text citation system and its presence is very strongly felt in the field of psychology and education and hence people researching on psychology may still feel comfortable with this form of citation but globally the preferred system is as end notes or footnotes.
As there are multiple citation styles which are followed in academic documents, they might be contemporaries to each other but every university has their own guidelines. I believe, each citation style is perfect on its own and thus it is quite acceptable to work as per the described guidelines.
There is no single style that is best, each has its own technicalities and requirements, however, APA is the most widely followed