Afghan is the name Persians have used for Pashtuns/Pakhtuns. Similar to as Pathan is the name Indians have used for Pashtuns/Pakhtuns.
These are all ethnic names.
None of these are neutral names. Khyber, Abaseen would be neutral.
One interesting fact is that in spite of the propaganda of ANP, most Punjabis that I have met support the name Pakhtoonkhawa as they are ignorant of the meaning of this name. Most Punjabis think if you live in Peshawar you are automatically a Pathan. They don’t even know that in Kohat, DIK and Peshawar Hindko is spoken.
One should also look into the ethnic conflict in Afghanistan where a century ago the name Kingdom of Kabul, Kingdom of Balkh was changed to Kingdom of Afghanistan. About 50 years ago it gave rise to ‘Afghan Millat’ party which started claiming that Tajiks/Uzbeks/Hazarajats are immigrants to Afghanistan. While the fact is that Kabul and north of Kabul the areas were collectively known as Khorasan.
This is also happening in Pakistan where Wali Khan of ANP had declared that non-Pashto speakers in NWFP are immigrants while the Afghan Muhajireen are locals!!
We are not too far from being an Afghanistan.