The cloth sim in Blender remains one of the most frustratingly un-updated features. I would dearly love to see it get an algorithmic refresh.

At least solver seems faster (if not better) in later versions? p.s. My try at 'flag in the wind' in Blender from around 2022: https://0x0.st/s/aJ6DNj2pEHzRdBiscEIsbQ/KCsK.mp4 I do remember it took me all day to get somehow realistic motion.