Because ethnically, they are Indo-Aryan,
Precisely. Which makes them Indian. And not Persian. Also ethnically Bengalis and Sinhalese are "Indo Aryan".
non of them are Dravidian.
Dravidian is a regional, linguistic or cultural term. There is only one Indian "ethnicity" truthfully speaking. Indians otherwise identify themselves based on their regional/language group as "Punjabi", "Gujarati" so on and so forth. It's a sub-ethnicity. It has no bearing on race as it would seem as you make it from the rest of your post. Dravidian is not the exclusive Indian sub-ethnicity. Both "Indo-Aryan" and "Dravidian" are more linguistic, regional and cultural terms. But in essence, Indian culture is what is shared by both "Dravidian" and "Indo-Aryan" groups even though they speak unrelated languages. South Indians generally have a pastoral-farmer culture similar to the rest of Indians difference is that their culture has Austro-Asiatic influence and that its a regional variant.
Punjabi is an Indo-Iranian language.
Ok?
And Punjabis and Iranians are the purest stock Aryans.
Firstly it is hard to say what an 'Aryan' is racially. If you are speaking of language, then almost all Indo-European languages of today still are a continuum of their roots and hence "pure". If you are speaking of culture, then the same can be said as well. If you are speaking of ethnicity, then all native Indo-European speaking European and native Indo-Iranian speaking countries might be pure in that sense. And Iranians are highly Arabized in almost all respects.
While most non Punjabi Indians have an admixture between Indo-European-speaking groups and Dravidian-speaking groups.
I don't know what you are talking about. But of all Indians it seems that Punjabis have had the most external influence due to the location of Punjab. But bottomline, the base of their culture is "Indian". Racially Punjabis have the most 'non-Aryan' influence for Indians apart from Tibeto-Burman and Austro-Asiatic. Racially Punjabis have Semitic influence. Punjabis cant have "Indian admixture" which denies them of their Indianness because
they are Indian. Both Indo-Aryan and Dravidian culture is
Indian. And Dravidian is distinct from Austro-Asiatic (which I think is what you are meaning by the lack of admixture in racial terms.) Only Tibeto-Burman is foreign.
The Indo-Iranians today are subdivided into the Iranian peoples, the Nuristani people, and the Indo-Aryan peoples..
No disagreement there. And Punjabis fall under "Indo-Aryan" and not "Iranian". Hence linguistically Pashtuns and Iranis are most closely related that way.
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