If we go by Islam itself, then these allies of the Gurus or their followers were not even Muslims.
"By the theory of it's origin the Muslim state is a theocracy... In such a state, infidelity is logically equivalent to treason... Therefore, the toleration of any sect outside the fold of Orthodox Islam is no better than compounding with sin... The conversion of the entire population to Islam and the extinction of every form of dissent is the ideal of the Muslim state."
- Sarkar, "History of Aurangzeb," vol. III, pg. 248-250.
According to the Koran, "the only faith acceptable to Allah is Islam."
-3:19.
What did Guru Nanak Dev Ji think of Islam?
"Make kindness thy mosque, sincerity thy carpet of prayer; what is just thy Koran; modesty thy circumcision; civility thy fasting and so shalt thou be considered a true Muslim."
- AGGS Ang. 140.
This was directly a challenge to Islam and it's elitism. Dismissed was the mosque, dismissed were the five prayers and the necessities of circumcision, dismissed was the Koran in it's stead a new and more humane formula was created.
Yet we still go by the imbecility, respect all faiths. Are we really to respect such faiths where inhumanity is rife? Did our Gurus? Jahangir and Aurangzeb were following Islam when they were committing atrocities (which of course Muslims are attempting to veil through inauthentic sophistry) and our Gurus raised their voices and arms against them. Were our Gurus wrong because they did not respect all faiths? The Vedas, and Hindu scriptures emphasize social stratification on a religious basis i.e. Caste. Were our Gurus wrong in raising their voices and arms against such a system?