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Suggesting that intellectual mindsets are necessary to create behaviours relies on our intellect being our ruling aspect. This does not seem true.
The intellect is never a truly objective entity and will always interact with subjective reality.
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On reflection, it seems some arguments are based on the assumption that the intellect is the base cause for behaviour or morals.
This seems a weak point and has no necessary validity.
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Let's examine base human behavior and morals when you strip away all "intellectual mindsets"
In a base state each person would have a right, or license, to everything in the world. There is no centralized authority and no external recourse against violence, coercion, or defection. Thomas Hobbes envisioned this as, a "war of all against all"
In such condition, there is no place for industry; because the fruit thereof is uncertain: and consequently no culture of the earth; no navigation, nor use of the commodities that may be imported by sea; no commodious building; no instruments of moving, and removing, such things as require much force; no knowledge of the face of the earth; no account of time; no arts; no letters; no society; and which is worst of all, continual fear, and danger of violent death; and the life of man, solitary, poor, nasty, brutish, and short.
Now it is likely that we do have a 'built in' primitive moral code that allows us without any preconceptions to escape Hobbs baseline. This code is one of tribalism.
One only has to look at how non-intellectual life exists to see the wrongness of an apparent "war of all against all".
There are myriad examples of cross-species interactions and non-parisitical behaviours, also inter-species interactions which are benevolent.
I also say you cannot escape the nature of mankind as being intellectual. Any "tribalism" is an intellectual construct, that any society which may exists as tribal, does so intellectually.
Before Newton "discovered" gravity, no-one noticed it. Before the 4 minute mile was broken, no-one could do it. But once these realisations became public knowledge it was not possible to undo these.
Your idea of tribalism should be expanded to acknowledge major social/cultural advances that have occurred. But I suggest it is impossible to do anything but hypothesise an unknowable base level - possibly useful for amusement but of no real use as it's too abstract to become useful.
What Hobbs describes is a war of survival. Obviously when there is lack there will be competition. This does not require a base level of survival war as the root of man's behaviour.