> I'm still surprised by the difference with the chess world where all the strong engines are free and open-source. FWIW, this is a fairly recent thing in ches

> I'm still surprised by the difference with the chess world where all the strong engines are free and open-source. FWIW, this is a fairly recent thing in chess (within the last decade). Before 2015 or so closed source commercial engines were better than open source options.