From [Cambridge Dictionary...][1]

> **bite** noun  
...  
 (STRONG TASTE)  
 *If food has bite, it has a sharp or **strong taste** - e.g. I like mustard with bite*  
...  
 (STRONG EFFECT)  
 *a **powerful effect** - e.g. This satire has real bite*

Note that the second definition is effectively just a metaphorical extension of the first, which itself is extended from the "literal" sense of the verb ***bite = use one's teeth to cut into something***.

---

I don't know the full context of OP's cited usage, so I can't say for sure which of those two definitions applies. But Zoe is probably expressing disappointment that the profile lacks metaphorical [**"punch"**][2] - *the power to be interesting and have a strong effect on people*.

---

Note that the construction ***There's no X to it*** is simply an alternative way of expressing the assertion ***It has no X*** or ***It lacks X*** - usually restricted to contexts where one might reasonably *expect* X to be somehow associated with whatever "it" is.

  [1]: https://dictionary.cambridge.org/dictionary/english/bite
  [2]: https://dictionary.cambridge.org/dictionary/english/punch