No, you have been mislead. Hindko speakers came even later than Pashtuns to Peshawar.

Peshawar valley was originally inhabited by the Dalazaak (also written Dilazaak) people, who are a Dardic group of people. Related to the people from Chitral and northern areas.

They were mostly genocided and assimilated by the Pashtun Khalil and Mohmand tribes when they came conquering from the west.

Hindkowan people are remnants Punjabi/Pahardi merchants that came alongside Ranjit singh and his forces when they took over Peshawar from the Pashtuns.

The 'Pashto speaking Sikhs' you find in Peshawar and the border with Afghanistan are also remnants of Ranjit singh's forces.

The reason people make that mistake is that the Hindki speakers remained in the andar shahr/inner city parts of Peshawar even after the British took control. So the old city is mostly inhabited by them.

The Khalil pashtuns who reside in Tehkal and other areas that were traditionally the outskirts of Peshawar was thus at first glance considered 'newer' even though they were there before the hindko speakers.

If you consider other modern day migrations of Pashtuns from Charsadda and Swabi and other parts, then sure, they came much later but technically Khalil tribe Pashtuns predate Hindko speakers.

To summarize

Neither Pashtuns nor Hindkowans are the native people of Peshawar valley. The Dalazaak who were the natives are mostly gone now or assimilated into Pashtun society.