[MC-195508] Wall signs held by endermen or block display entities are not rendered

The Bug
When doing

/summon minecraft:enderman ~ ~ ~ {NoAI:1,carriedBlockState:{Name:"acacia_wall_sign"}}

The enderman doesn't render it despite it being able to render wall_torch

/summon minecraft:enderman ~ ~ ~ {NoAI:1,carriedBlockState:{Name:"acacia_wall_sign"}}

Wall signs don't render when held by endermen.

Wall signs would render when held by endermen.

Linked issues

Hi there!

I can confirm this for 20w29a (I didn't test it in 1.16.1).

Can confirm in 20w30a.

Can confirm in 21w03a.

Can confirm in 21w05b.

Can confirm in 21w06a.

Can confirm in 21w07a.

Can confirm in 21w08b. Video attached.

Can confirm in 1.17.1.

Can confirm this behavior in 21w42a. Here are some extra details regarding this problem.

The Bug:

Wall signs don't render when held by endermen.

Steps to Reproduce:

/summon minecraft:enderman ~ ~ ~ {NoAI:1b,carriedBlockState:{Name:"minecraft:acacia_wall_sign"}}

Look at how the enderman's arms are held out, indicating that it's holding something.
Take note as to whether or not wall signs render when held by endermen.

Observed Behavior:

Wall signs don't render when held by endermen.

Expected Behavior:

Wall signs would render when held by endermen.