I don't know how well known he was internationally @bobhaugen so you may not be as out of touch as you fear. His book Capitalist Realism: Is There No Alternative is short and very good if you are curious to learn more about his thinking.

He hit controversy over an essay he wrote as a public farewell to social media - parts were I think very badly misjudged and hurt people he did not want to hurt. There is still bad feeling about that unfortunately and while I don't want to dredge it up with links now, if you go looking for information on him, you will find them. He was a good person. Thoughtful and sensitive. The world is poorer without him.

Thanks @IBob I've skimmed the first few paragraphs and put aside to read later. It feels ironic to see that in a newspaper I stopped reading with great relief a couple of years ago precisely because the Guardian these days feels like a manifestation of the "Vortex" Oliver Burkeman describes!