Well, considering that the Arthurian legend dates from the 14th Century, some semi-forgotten 80s flick can hardly be called the true inspiration for the current movie
THE GREEN KNIGHT (2021) - Based on the Arthurian legend Sir Gawain and the Green Knight, Writer-Director David Lowery gives this telling his trademark meditative style based more on visuals than plotting. Action taking a back seat to ambiance.
Dev Patel (quite good) plays young immature Gawain...