Quite simply, if you don't find the main character likable nor interesting then the entire film depends on it. Many may like it, but I found it tedious.
I had the same problem relating to characters in 'Before Sunrise' and its trilogy. My own personal issue here, is the entire films are based on the characters and the relationships, which shows clearly that Linklater's youth relationships rarely struggled to hardship, poverty etc.
All his films are people who have had solid foundations, education and financial support from others, slightly above middle class, hence watching these characters have yet experienced real challenges in life.
On top of that, if you have not looked at the trilogy of Apu, you would be embarrassed by comparing this boys life to 'Boyhood'.