EntityTag doesn't work on all items summoning entities

Some items summoning an entity when used don't apply the EntityTag tag to the summoned entity.

Affected items

• Item Frames (19w07a)
• Paintings (19w07a)
• Minecarts
• Boats
• End Crystals
• Fireworks
• Throwable items (Ender Pearl, Snowball, ...) (Should also work with dispensers) (Lingering potions could have their changes stored in themselves as thrown potions aswell as in the area effect cloud they will summon)
• Arrows (If an arrow item is being used which has the tag)
• Leads (
• Maybe even fishing bobbers when summoned using a rod which has the tag (for consistency)

How to reproduce

• Run the command:

  /give @s oak_boat{EntityTag:{Tags:["test"]}}
  

  -> When placed, the entity summoned does not have the tag test.

Original Description

I'm not sure if this is just a bug or works as intended but I noticed that giving item frames an "EntityTag" tag won't apply any changes when you place them.

I feel like all items summoning entities should support the "EntityTag" tag. I don't see why it should only work for armor stands & spawn eggs. It can be useful for all entities.