"When I was a child, I always dreamed of becoming a dancer."
Translation:Kiam mi estis infano, mi ĉiam revis fariĝi dancisto.
To put it in another light, "-iĝ" added to a verb makes that verb "intransitive". Intransitive verbs do not have a direct object. So it's not confined to just the verb 'fariĝi'.
I wouldn't say it makes the verb intransitive, i'd say it makes the verb a noun one (as we say in portuguese), which mean, this verb doesn't imply action, so whatever comes after it is a subject predicative.
Why can't it be "mi songxis"? Why does it gotta be "revis"? Isn't "revi" and "songxi" the same?
A sonĝo is a dream like you have when you're asleep. Revo is more like a goal. So sonĝi means to have a dream at night, while revi is to plan something that may or may not happen in the future.