Weardear

I really don't think this disproves the theory. The WoB just says that the shards aren't paired. This chart agrees, each shard would share up to three characteristics with other shards. Ruin and Preservation share two of these three attributes, but also their intents just make them opposites by nature. However, with this theory, you could also argue that Cultivation was the opposite of Preservation, because she encourages other things to change over time, while Preservation encourages things to stay the same over time. So each shard wouldn't have a perfect pair, just several shards that they shared characteristics with.