No, not much true.
Both Ottomans and Seljuks knew they were Turks and openly stated that, its just lets say they were not much enthusiastic about ethnic stuff.
On Ottomans perceive of Turks, well its not that simple, as I said in my older posts, there was even a kind of proto Turkic nationalism in early Ottoman period until end of the 15th century, why a negative attitude started among Ottoman upper class in following periods ?
1)Political, almost all of the main enemies of Ottomans in the east were Turkic(roughly), Karamanids, Timurids, Akkoyunlu, Safavids, there was also a constant unrest in Anatolia, mainly caused by Turkic nomads.
2) In addition to these, Ottomans were now a multiethnic empire, they didn't needed claim for rule, they didn't needed to strictly bound themselves to a certain ethnicity, especially an ethnicity that does the stuff in 1).
3) The negative attitude was againts the semi-nomadic, rebellious life style, rather then the entire ethnicity itself, that attitude was not just againts Turks, but other similar people as well.