[2021] What is up with custom blueprints?

Correct me if I'm wrong, but you can now equip attachments that you haven't unlocked yet. To test this, I purchased the "Entrenched" bundle from the store that included the "KGB Skeletal Stock" attachment for the AK-47. I can now equip this attachment to my base AK (not the blueprint it came with from the store) even though I have not unlocked the base attachment? It would seem if you buy a bundle from the store, you buy attachments as well. It was different in Modern Warfare 2019, as you couldn't equip the individual attachments unless you'd unlocked their base.

TL;DR I can buy a level 54 attachment from the store for 800 CP and equip it right away in custom blueprints even though I'm nowhere near to unlocking it...

Long story short, gunsmith custom blueprints still broken?

EDIT

I have spoken with Activision Support and confirmed officially that this is intended behaviour.