The lore states that dragons pick their mortal forms essentially to blend in better with mortals. Be it to look through "the eyes of younger races", spy reasons, or to be more familiar to the races they're interacting with so they can interact with them better. The specific form they pick on top of that can be what is closer to their personality.
Don't see how Drakonids fit into that at all. We've never seen a single dragon pretend to be a dragonkin. Not even in the most obscure places of lore or non-canon sources.
If blizzard was about giving players options we'd have less class restrictions.I'm all about giving players options.
But in the end the debate is pointless because you'll see on the 19th that we won't be actual dragons because of the several lore & mechanical reasons.
Only exception might be a dragon form mount for some reason, but mounts aren't actual canon so it's ok.
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I just hope if we get a dragonkin/drakonid/dragonman race it has a unique skeleton compared to existing playable races with unique animations.