Cannot give named items with new syntax and entities only accepting names "true, false" and anything composed only of 0-9

Whenever trying to give a player an item, I've been following the new syntax and it has not allowed me to name the item.

/give <Username> minecraft:diamond_sword{display:{Name:"Sword of Sharpness"}} 1 does not produce a Diamond Sword item named "Sword of Sharpness".

Further more, when attempting to summon a Sheep named "jeb_" does not work.

/summon minecraft:sheep ~ ~ ~ {CustomName:"jeb_"} does not produce a Sheep named "jeb_"

/summon minecraft:sheep ~ ~ ~ {CustomName:"true"} and /summon minecraft:sheep ~ ~ ~ {CustomName:"false"} as well as a name consisting of digits work as well, Ex:
/summon minecraft:sheep ~ ~ ~ {CustomName:"11"}

If this is not a bug, why do the words true and false still work?
/summon minecraft:sheep ~ ~ ~ {CustomName:"true"} summons a sheep named true.