I dont know if this is a bug or not but there should be netherite horse armors
Comments 2
Thank you for your report!
However, this issue is Invalid.
You have posted a feature request or a suggestion. This site is for bug reports only.
For suggestions, please visit the Feedback website.
Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Customer Support – ✍️ Feedback and Suggestions – 📖 Game Wiki
That is a feedback so you can post it on https://feedback.minecraft.net/hc/en-us