Animation interpolation type getting overriden when reopening engine

Godot Version

4.2 and 4.3

Question

Hello!
Im trying to import all the animations on a blend file, and then applying the Nearest interpolation type to all the tracks using a tool script:

@tool
extends EditorScenePostImport

func _post_import(scene):
	var animationPlayer : AnimationPlayer = scene.get_node("AnimationPlayer")
	interpolation_change(animationPlayer) # run the funstion in question
	return scene

func interpolation_change(animationPlayer):	
	var animationList = animationPlayer.get_animation_list()
	for animationName in animationList:
		var animTrack = animationPlayer.get_animation(animationName)
		var count  = animTrack.get_track_count() # get number of tracks (bones in your case)
		for i in count:
			animTrack.track_set_interpolation_type(i, 0) # change interpolation mode for every track

After importing, all tracks are the correct type

But after reopening the engine, they get all messed up

I have tried storing my anims in an animation library, skipping export on the anim player and adding one by hand (so its not tied to the blend scene), changing the type manually, etc. And no clue, every time I open up the engine again, the interpolation is totally mixed.
What I am missing here? It has happened in 4.2 and 4.3 the same
And, also, I dont understand the “Imported Scene” warning at the bottom, im working of saved-as-resource animations and already have the “save to file” and “keep custom tracks” import settings checked

Have you found a solution for this? I am having the exact same issue.