the comparison with netflix is a little misleading, i think, because there's a much clearer difference between films than their is between wines (famously, people have rated white wine + dye as red wine with no problems).
pulling numbers out of my ass i would guess that grape variety, colour / tannin content, sugar concentration and acidity would cover all you needed if context wasn't so important. but context does dominate, so if you have faith in the site you'll enjoy whatever it says it is good...
[actually, the more i think about this, the more i like the idea of something like you suggest based only on hard numbers for factors like i gave. if nothing else, it would be a lot of fun following different trails...]
pulling numbers out of my ass i would guess that grape variety, colour / tannin content, sugar concentration and acidity would cover all you needed if context wasn't so important. but context does dominate, so if you have faith in the site you'll enjoy whatever it says it is good...
[actually, the more i think about this, the more i like the idea of something like you suggest based only on hard numbers for factors like i gave. if nothing else, it would be a lot of fun following different trails...]