The original Oty from D&D seems much, much larger than ours. Its tentacles were so filthy even just a touch could send any creature into a systemic shock, known as filth fever. No wonder either, as it lived in the sewers and fed on rotten offals. It kills it foe and saves the innards until they're rotten; that's just how it likes it.
But our Oty is not this Oty. Ours is clearly much less fearful, looks smaller, and even if the D&D Oty could possibly catch some low-flying creatures, ours doesn't look like it could. Nevertheless, I don't think any change to the bonus given when devouring can make up for removing its ability to Devour airborne, mainly because so many creatures are indeed airborne.
I also find Oty balanced.
