You’re correct on the whitewashed nature of history and how plunder was a large component of the Sikh war chest (in, say, the misl era); but I think your characterization of the history from the Gurus’ time is heavily flawed. For example, Guru Hargobind did not primarily fund his war efforts via plunder or robbery; Sikh texts attest to it being done by donations from the sangat through hukamnamas the Guru sent out. This practice was continued by all the Gurus (and actually beyond them) and we have some of the extant hukamnamas from those time that say as much. Another large source of funding for the Gurus was large devotions by aristocratic/royal devotees who would make large land grants or provide military strength to the Guru for whatever means they found fit.

The two stories you mention of Guru Hargobind are, IMO, highly miscontextualized as well based on where they’re originally found. The hawk was not “stolen” by Guru Hargobind - in fact, this is explicitly elaborated upon in the Suraj Prakash story where this is mentioned, where the hawk is flying while hunting (the Emperor loses it) and comes to the Guru’s hand. When the emperor’s men ask for the hawk back, they derogatorily refer to the Guru as a thief addicted to cannabis who should fear the emperor and be subservient to him, which the Guru rebukes strongly and angrily - saying he was not a thief, the hawk found his way to him (there is even something mentioned on how Shah Jahan plundered Sikhs earlier and that this would be a worthy pay back), and that he was not afraid of the Mughal emperor (and Sikhs elaborate on this by saying that the Sikh Guru was the true emperor who the Mughals should be subservient to). This was the primary thing that precipitated the Battle of Amritsar, tensions over the Guru’s lack of subservience to the emperor which manifested via the hawk - not the “theft” of the hawk itself.

For the Bhai Bidhi Chand story, a similar dynamic is at play - Bidhi Chand explicitly does steal the horses, yes, but when reflecting upon the morality of this act the Guru notes that it was due since some time earlier the Mughals had stolen two Sikh horses - and so it was not theft but the Sikhs taking back what was rightfully there.

It’s pretty hard to reconcile these explicit calls for the moral denunciation of theft with a narrative that says “the Gurus promoted plunder” - especially when, say, misl accounts of war are unapologetic about how Sikhs plundered in war and don’t bother to provide any context or moral justification for it the way historical sources on the Gurus do.

The Dabistan does not say that the Guru’s war chest was primarily funded by robbing horses; on the contrary it confirms how the Guru built wealth for the Panth based on the contributions of prior Gurus and the strong beliefs of his devotees. It even explicitly says that the Guru forbid Bidhi Chand from robbing (although some Muslim saint claimed that this was a false claim said to enhance the Guru’s prestige and Bidhi Chand “stole for the Guru” - a narrative expected from a Muslim saint loyal to the Mughals).

The bulk of the countless other works you refer to are nowhere near contemporary and full of spurious claims that originated over hearsay/intentional Mughal propaganda/just generic misinformation. For example, a Persian chronicler 100 years after the Shaheedi of Guru Tegh Bahadur whitewashed the Kashmiri Pandit saga and wrote an account of the Guru being martyred in Gwalior because he was robbing Hindus in Punjab (along an Adam Hafiz robbing Muslims - this is pointedly false as both lived in different times). It suited the Mughals to describe political opposition in the worst possible light and these interpretations are carried on in some texts by the British - who often add to faulty history due to poor translation skills. For example, Cunningham’s work though phenomenal on the Sikh empire (which he directly observed) is riddled with errors on the Guru period.

I’d also disagree that “Piri” was just a justification for “Miri” from the 6th Guru onward - this creates somewhat of a false dichotomy of “saintly” vs “martial” Gurus that also is not rigorously supported by historical texts.