I've been teaching on Italki for about 5years now without prior experience. It started as a hobby but once I started to like it I got serious and put some teacher training under my belt. Prices have gone up from when I started to the point where I am now. It certainly is seductive to see it as a quick buck but the students soon will see if the teacher is legit or not.
The past 3 years I lived in Indonesia and although I had another teaching job there as an English teacher, it was not a fixed monthly salary as a freelancer, so i was happy I could still teach on Italki to make a living.
I think prices might lower due to a new group of teachers with low experience but the teachers who were here longer have more experience and in my case will not lower the prices. I don't see the new teachers as any competition. In fact I've raised my prices. Because I once learned during a business class that if you're good at something, never do it for free or a low price, so don't let a situation like this intimidate you. Just my 2c
