Witold Lutoslawski gave his native musical culture the highest that an artist can create: The pinnacle of modern musical creativity. People who don't know Witold Lutoslawski's music can't understand Polish music or measure it.
The spiritual task that Lutoslawski took on became his most important contribution to the history of universal music. That task was to develop musical thought in a fundamental and rigorous way, freeing it from inherited norms of tonality and not leading to the destruction of total logos. He gave the answer with his works.

He created a musical form that was new in its kind. And that means feeling music - and the world in general - differently. We can settle into this music. 

Michał Bristiger [1994]

In this music, full of discretion and dignity, no ear will hear falsehood, including moral falsehood. [...] His music is pure - like the “tears of the poor man,” like the Lausanne Lyric. Pure in the sense in which Mozart's music was pure, that is, music that is joy itself, “the spark of the gods,” which in Lutoslawski's case means: consolation. [...] reflected in it, as in a spring, that part of the Polish fate which is connected with the tradition in which we, from below, and we, from above, most fully recognize ourselves. Honest as a “widow's mite” she is simply the true face of Polish music.

Krzysztof Karasek [1988]