Unselfconscious accessibility

Hi there. I can not understand what the following extract want to say Can anybody please help me with it? For example, what does "unselfconscious accessibility" mean? What is the difference between being socialist and demotic or what do "that is to say of the people" and "It is also idiomatic, speaking the language of a particular group or individual" mean?

Text:

For Newman, the unselfconscious accessibility of Wearing’s art fits the cultural ethos generated by New Labour which is not so much socialist as demotic, that is to say of the people. It is also idiomatic, speaking the language of a particular group or individual.