Does Disintegrate no longer dusts the Wild Shaped Druid?

You have a huge creature and a druid, shaped to a water elemental, stops in its space. Can that huge creature attack the elemental druid?

Is that intentional so a third party can be either your ally or only the enemy of your enemy?

How does a Spelljammer helm work in 5e?

Beast Master companions feature says they add proficiency bonus to “any saves… they are proficient in” but…