Bukhari

Hadith Commentary:
And as long as they uphold the religion.
If they abandon the religion, then the matter of caliphate will be handed over to other nations.

Hadith Commentary:
➊
This hadith indicates that as long as the Quraysh exist, they will be entitled to the caliphate. However, it is necessary that they be the standard-bearers of Islam and take practical steps for its implementation; otherwise, they will be deprived of this caliphate. Thus, the noble statement of the Messenger of Allah (sallallahu alayhi wa sallam) is:
"This tribe of Quraysh will bring people to the brink of destruction."
The people asked:
"O Messenger of Allah (sallallahu alayhi wa sallam), what is your command for us in such circumstances?" He replied:
"Would that people separate themselves from them."
(Sahih al-Bukhari, al-Manaqib, Hadith 3604)
Because at that time, instead of upholding the honor of Islam, they will be overcome by the greed for dominion and will fight and wage war for worldly gain.

➋
In any case, Imam al-Bukhari (rahimahullah) has established from this hadith that the Quraysh are entitled to the caliphate, provided they maintain the standard that the Messenger of Allah (sallallahu alayhi wa sallam) has stated.
After the passing of the Messenger of Allah (sallallahu alayhi wa sallam), Abu Bakr al-Siddiq (radi Allahu anhu) and Umar al-Faruq (radi Allahu anhu) used this very criterion to silence the Ansar. Their position was that one leader should be appointed from the Ansar and one from the Muhajirun; then all the noble Companions (radi Allahu anhum ajma'in) agreed upon the matter that the caliphate is the exclusive right of the Quraysh. However, the Mu'tazilah and the Khawarij differed on this.
And Allah knows best.

Hadith Commentary:
Imam Nawawi rahimahullah has said that it is clearly derived from this hadith that the caliphate is exclusive to the Quraysh, and until the Day of Judgment, it is not permissible to pledge allegiance (bay‘ah) to a non-Qurayshi for the caliphate. During the time of the Companions (radi Allahu anhum), there was consensus (ijma‘) on this matter. And if, in any era, a person from any other nation besides the Quraysh happened to become king, then he did so with the permission of the Qurayshi caliph and remained as his deputy.
(Wahidi)

Hadith Commentary:
From this hadith, it is clearly understood that the caliphate is exclusive to the Quraysh, but this entitlement is conditioned upon the establishment of the religion. Therefore, when the caliphs showed weakness in matters of religion, circumstances changed, and as long as these Qurayshi individuals uphold the religion correctly, leadership will remain among them, even if their number is only two.

It is narrated from Abu Hurairah radi Allahu anhu that the Messenger of Allah sallallahu alayhi wa sallam said:
"The Hour will not be established until a man from (the tribe of) Qahtan appears who will drive the people with his staff."
(Sahih al-Bukhari, Al-Fitan, Hadith: 7117)

Upon this, Imam Bukhari rahimahullah established a chapter heading that circumstances will change until idol worship begins again.

Until this change occurs, the Quraysh alone will be entitled to the caliphate.

In the present era, although the Quraysh are not rulers, nevertheless, no one has the right to deny their entitlement.

The Messenger of Allah sallallahu alayhi wa sallam, in the aforementioned hadith, did not inform of an incident, but rather gave a ruling that governance should remain among them.

And Allah knows best.