Class means a lot to the apologists for capitalism. They are very keen to say it doesn't exist. If the slaves don't think they are slaves then they won't revolt.
No classes is the aim of the socialist.
In capitalism, classes mean a minority own the means of living and live in unearned luxury, all at the expense of the non-owning, exploited, majority of wage slaves. A truly classless society is when the means of living are held in common and used to meet human need.
Class society is the social ill at the heart of our problems.