Of course I wouldn't pick it just because someone likes it, but it's still... data. Data that I'll combine with other sources of data. It provides a small but non-zero amount of weight to one side. Aka it is not useless. If you see patterns in people's unjustified recommendations, it starts to be a lot more than non-zero.

Your take appears to be: "for an idiot reader who will do exactly what they're told, this information is useless". Well! The readers aren't idiots. Easy.