Hello! So, apparently the enchantment glint on horse armor added in the previous snapshot was somehow disabled in the current snapshot. That's all.
MC-276604
Horse Armor no longer has enchantment glint
Resolved
Fixed
7
Community Consensus
Platform
Low
Rendering, Textures and models
24w37a
1.21.2 Pre-Release 1
Retrieved
Can confrm. Seem to be due to the fix of MC-276299.