ワクワクする vs ワクワクしている


What is the difference in actual meaning/usage?

The example is from <https://hanasu-eigo.com/2017/01/11/325/>

> “I’m excited!” というのは、「すごく楽しみなことがあってワクワクしている」というような時に使います
>
> and then had an example below:
>
> “I’m going to Japan for the first time. I’m so excited!“
>
> 初めて日本に行くの。すっごいワクワクする！

I've read and listened to enough that I would know if someone was excited
about something, but if I used the words themselves, I imagine I would end up
using ワクワクしている more often than natives would (where they would simply use
ワクワクする).

