Generic Foreign Key on unsaved model in Django

I have stumbled into a bit of inconsistency with Foreign Keys and Generic Foreign Keys in Django. Suppose we have three models

class Model_One(models.Model):
    name= models.CharField(max_length=255)

class Model_with_FK(models.Model):
    name=models.CharField(max_length=255)
    one=models.ForeignKey(Model_One, on_delete=models.CASCADE)

class Model_With_GFK(models.Model):
    name=models.CharField(max_length=255)
    content_type= models.ForeignKey(
        ContentType, on_delete=models.CASCADE,
    )
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey("content_type", "object_id")
    class Meta:
        indexes=[models.Index(fields=["content_type", "object_id"]), ]

When we do

one = Model_One()
two = Model_Two(model_one=one)
one.save()
two.save()

Everything works okay. Model one recieves an ID, and when model two is saved, that ID is used to reference model one. However, the same does not work with GFK

one = Model_One()
two = Model_With_GFK(content_object=one)
one.save()
two.save()

When there is an attempt to save two, integrity error is raised that "object_id" column is null. When inspected with debugger, as soon as model one is saved, field "content_object"on the model two is turn from model "one" to None. This is quite unexpected, as with Foreign Key there is no such problem.

Of course you can save model one before using it in GFK relation, but why is this necessary? With Foreign keys, i could instantiate all the models and then create them with bulk_create. With GFK in the picture, this no longer seems possible

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