1) There's no way Chilean education is the most expensive in the world. Tuition for an engineering degree at the best universities in Chile is around USD 5k/year, which is way cheaper than pretty much any university in the US. (edit: in fact here's a ranking, and Chile is not even mentioned on it http://www.businessinsider.com/hsbc-australia-is-the-most-ex...)
2) The tax hike was a bust and it generated only around USD 2B, a fourth of what it was expected to bring in. Now they are saying they'll tax people for having a degree!!
3) There is no clear plan to actually implement free higher education. They increased taxes hoping to collect additional money from taxpayers (which didn't work), without knowing how they are going to use the funds.
4) Those students leaders that are now part of congress, deceived the people that supported them and are now supporting completely different things than what they said they would when they were leading the people that got them elected. They basically sold out.
5) The article is from February. Only 2 days ago, the president of Chile announced she was asking for the resignation of all of her ministers. No one knows what will happen next.
6) Even though education in Chile is not the most expensive in the world, it has the highest paid congress people in the world, and they just approved an increase of seats!! Talk about inequality (they make around USD 300k/year, when the average salary in Chile is less than USD 5k/year)!
I'm all up for free education for everyone, but the way the Chilean government is doing it is definitely not the way to go.
PS: all discussions about educational reform in Chile are so short sighted that no one has even touched on the subject of online/virtual education and making education cheaper and more efficient.