Besides the fact that this also was quite a bloody period of Icelandic history, the population also most probably was below 50000, which is the census result of 1703.
If you have no population to speak of, and practically everyone is a subsistence farmer/fisherman, and you have a population density of about one person per square mile, then yes, you don't much coordination/government.
If you have no population to speak of, and practically everyone is a subsistence farmer/fisherman, and you have a population density of about one person per square mile, then yes, you don't much coordination/government.