Acceptable references are provided in multiple meta posts such as Guidelines for new users answering questions, What kind of references are valid in answers? Are modern works allowed? and Which scriptures / sources are considered valid?
In short, this site allows quotes from direct Scriptures (Vedas, Agamas, Puranas without any commentary) to Scholarly Works and words of all Hindu Saints. But users may prefer answers with direct scriptures as references more than Scholarly works or words of saints as references for the same question.
(1) The allegation of "Tamasic Puranas" which non-sectarian modern scholarship has rejected. Are posters allowed to say evidence from some purana can be rejected a priori because it has been dubbed a "Tamasic Purana"?
Hinduism has many philosophies and many sects and this site allows beliefs and opinions of all Hindu sects. Concept of Tamasic Purana is rejected by some sects but it is believed to be genuine by some other sects. Every sect in Hinduism has different opinion on different issues. We have to respect all their beliefs. So, this site accepts opinions of all sects on "Concept of tamasic Puranas".
If you personally feel an answer is incorrect, downvote the answer. Stack Exchange sites (of which Hinduism SE belongs) are Q&A sites, not discussion forums. Even comments should be used only for asking clarifications and suggest corrections on posts (questions and answers) and many comments become obsolete when they serve their purpose. If users want to discuss any topic, they may discuss in chat rooms.
2) Alleging Puranic material to be "interpolations" without any scholarly argument. Also using lack of citations in later works arbitrarily - saying that it is evidence of interpolation in some cases and giving convoluted explanations in other cases.
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