Bukhari

Hadith Commentary:
This hadith has already been mentioned above.
Hafiz Ibn Hajar states that there arises a problem here: the people of Banu Tamim came in 9 AH, whereas the Ash‘aris came earlier, in 7 AH. He has answered this by saying that it is possible that some of the Ash‘ari people may have come even after Banu Tamim.

Hadith Commentary:
➊
Imam Bukhari (rahimahullah) has narrated this hadith in a very concise manner, whereas previously this hadith has been narrated in detail.
In that narration, it is mentioned that the people of Yemen had asked about the beginning of this universe.
(Sahih al-Bukhari, Book of the Beginning of Creation, Hadith: 3119)
➋
Hafiz Ibn Hajar (rahimahullah) says that there is a problem in this hadith: the people of Banu Tamim came to Madinah Tayyibah in the 9th year of Hijrah, whereas the Ash‘ari people had already come to the Messenger of Allah (sallallahu alayhi wa sallam) earlier, at the time of the Battle of Khaybar in the 7th year of Hijrah. How, then, was their gathering together possible? He then answers this by saying that some of the Ash‘ari people may have come after the Battle of Khaybar as well.
(Fath al-Bari: 8/123)

Hadith Commentary:
The reason for the displeasure of the Prophet (sallallahu alayhi wa sallam) was that they did not accept the glad tidings of the everlasting blessings of Paradise and instead sought the lowly world.
Whereas, if they had accepted the prophetic glad tidings, they would have received some portion of the world as well, but they became among those described as ﴿خسر الدنیا والآخرة﴾ ("he has lost this world and the Hereafter").
It is Yemen’s good fortune that its people accepted the prophetic glad tidings.
From this, the virtue of Yemen is also established, but the current civil war has stained Yemen.
Allahumma allif bayna quloob al-muslimeen, ameen.
Not all of Banu Tamim were like this; it was only a few individuals who made this mistake. The virtues of the rest of Banu Tamim are also mentioned, as will be discussed ahead.

Hadith Commentary:
The entire tribe of Banu Tamim was not like this; it was only a few individuals who made this mistake.
The Messenger of Allah (sallallahu alayhi wa sallam) became displeased because these people rejected the everlasting blessings of Paradise and instead demanded the insignificant wealth of this world. Had they accepted the glad tidings given by the Messenger of Allah (sallallahu alayhi wa sallam), they would have received much in this world as well. However, it is the good fortune of the people of Yemen that they accepted the glad tidings of the Messenger of Allah (sallallahu alayhi wa sallam).
From this, the virtue of Yemen and the people of Yemen is established.

Hadith Commentary: The Prophet (sallallahu alayhi wa sallam) gave the glad tidings of ultimate goodness to Banu Tamim because they had embraced Islam. The people of Banu Tamim, due to their lack of understanding, thought that the Prophet (sallallahu alayhi wa sallam) was someone who distributed worldly wealth and riches. This way of thinking caused the Prophet (sallallahu alayhi wa sallam) distress. It is said that the one who made this request was a man named Aqra’ bin Habis, a Bedouin.

Hadith Commentary:
1.
By "the people of Yemen" is meant the delegation of Himyar. This does not refer to Abu Musa al-Ash'ari radi Allahu anhu and his companions, because Imam al-Bukhari rahimahullah has established a separate chapter with the following words:
(Bab Qudum al-Ash'ariyyin wa Ahl al-Yaman)
"The arrival of the Ash'aris and the delegation of the people of Yemen."
(Sahih al-Bukhari, al-Maghazi, Chapter: 75)
This means that the Ash'aris and the people of Yemen are two distinct groups. In addition, Abu Musa al-Ash'ari radi Allahu anhu, along with his companions, came at the time of the conquest of Khaybar in the 7th year of Hijrah, whereas the people of Yemen came as a delegation in the 9th year of Hijrah in order to gain understanding of the religion. It was with this delegation that the Messenger of Allah sallallahu alayhi wa sallam had a gathering with the Banu Tamim; the Ash'aris did not gather with the Banu Tamim.
(Fath al-Bari: 8/122)
2.
The Messenger of Allah sallallahu alayhi wa sallam gave the Banu Tamim glad tidings of success in the Hereafter due to their acceptance of Islam. They, however, considered this to be glad tidings of worldly wealth and possessions. The Messenger of Allah sallallahu alayhi wa sallam was distressed at their greed and desire for the world, or he was saddened because they were new Muslims. He did not have any wealth with him to win over their hearts, so he became sorrowful. However, the first explanation appears to be weightier.
And Allah knows best.