hey were never relevant enough to matter in Poland or the US
In Poland, it's understandable. In the English speaking world or anywhere that English literature is studied, then their relevance is considerable. Every educated person will be familiar with the term 'First World War Poets' including anybody who has studied English literature in an American university. High school students in the the USA should have heard of them but largely haven't because you don't have a proper national curriculum and basic education is deficient and dumbed down.
In fact, war poetry is an entire genre of literature and every nation has produced its war poets.
"war poetry was produced across Europe, by poets as diverse as Giuseppe Ungaretti, Georg Trakl, Guillaume Apollinaire and Anna Akhmatova, and further afield from countries such as Australia and New Zealand, Canada, India, the West Indies and Turkey."
stupid and heroes die first
But not all of those poets died in the war. Many came back.