Optometry as a first choice at 17. Too narrow, or a sensible start?

Our daughter starts class 12 in June with biology and maths. Last week she said optometry is what she'd like to do. I work alongside optometrists every day, so I know what the job involves. What I can't judge is whether it's a good thing to commit to at 17. Part of my worry is that I see the work only from the clinic side, and she has only seen it through me. If your child chose a specific course like this straight after class 12, did they stay with it? And did keeping a broader option open alongside it make the class 12 year harder?