It's the opposite. Oda keeps shitting on him
1. Sanji was able to do what his siblings can do with Vinsmoke technology, except Sanji did it on his own. For example, Vinsmoke siblings can fly around with their special shoes, Sanji does it by learning Sky Walk. Ichiji can produce heat with Vinsmoke suit, Sanji can do it with Diable Jambe
2. Sanji said he doesn't wanna use it but now he ended up using it
3. The way Niji gave it to him was mocking and disrespectful