I somehow found this board again and bumbed into this thread. I am not here for long discussion, just going to give my understanding and opinion on this matter.
As I am from time to time also on the apricity I know the persons mentioned here and talked about and I already gave my opinion on this matter there too.
Afghans and Kurds
A major problem I see in all this unnecessary debate is that people have a hard time understanding the concepts of passing vs looking typical.
For example a certain Pashtun can pass and yet still not look like average majority of Kurds. This is made possible because among every ethnic people on this planet there is variation and as a result of that you will find even Kurds you won't assume to be Kurds on the first look.
Then a typical Kurd passing as an Pashtun doesn't automatically mean the Kurds look typically Pashtun. As there are even atypical Pashtun who look Russian.
I tried to explain this with a model on the apricity.
Let's Imagine 6 clusters (only 6 for the sake of keeping it simple). Let's call them simply A, B, C, D, E, F and they represent different phenotypes.
Among ethnic Kurds = A:45% B:20% C:30% D: 5%
Among ethnic Pashtuns = A:10% B:10% C:30% D:40% E:10%
Among Persians (from Iran) = A:25% B:45% C:15% D: 15%
Among ethnic Beluch = A:5% B:20% C: 20% D:40% E:5% F:10%
In this example 4 types exist among Kurds. All those 4 types are also found among the Pashtuns and in fact make up 90% of the Pashtuns population. While E: which is found among every 10th Pashtun is non existent among Kurds.
However despite the point, that 90% of the Pashtun population belong to types also found among Kurds, an important difference is the distribution of the types. While the type D is very atypical for Kurds. It makes up 40%! of the Pashtun population. Like 4 out of 10 Pashtuns is quite atypical for Kurds. At the same time the type A, which is very typical for Kurds and makes up almost half of the total population, is quite atypical for Pashtuns. This is a very significant difference. Despite on individual basis "90%" of Pashtuns being able to pass as Kurds (once again being able to somehow pass and being typical are two different shoes) only half of the population would pass without being perceived as too atypical.
Another thing to point out the images of rural Pashtuns are influencing the perception. It's experience.
Are Afghans West Asian?
Now do I consider Afghans as West Asian? Well If by West Asian we are talking about the whole Near East. I don't see how Afghans are genetically and lookwise further away from us than let's say Yemenites? However if with (Northern) West Asian we refer only to the regions of Anatolian, Mesopotamia, Iranian Plateau,, (Trans) Caucasus. Than it's a different story.
In my book and from my experience over the years, I have changed my opinion slightly on this matter. Formerly I would have said the Levant is part of what I would call Northern West Asia.
Nowadays I am at the conclusion that the Levant is a whole region of itself, genetically, as well culturally.
I personally divide the Greater Middle East in these regions.
1. Northern West Asians
Which would be Anatolia, (Trans) Caucasus, Iranian Plateau, Mesopotamia
3. Levante
Lebanon, Israel, Palestinian territories, South, West Syria (excluding North and Northwest), Jordania, Egypt
2. Western Central Asia or West-Central Asia
Which would be territories of Tajiks, Yaghnobis, Pamiris, Wakhis, Pashtuns, Beluch, Turkmens and possibly Uzbeks.
4. Arabian Peninsula
Saudi Arabia, Yemen, Oman, UAE, Qatar, Bahrain
5. North Africa
The Maghreb countries + Egypt
Egypt is mentioned twice because of it's bridge character both culturally and genetically.
I listed Pashtuns and Tajiks in a cluster which I called West-Central Asia. Why do I think this represents them best? Well they are mostly different from South Asia and the rest of Central Asia by culture, linguistics and even genetics. Though there are overlaps but you clearly can distinguish this group of people from their neighbours.