The Hadeeth about following the 'majority' refers to the early Muslims
26-10-2014 | IslamWeb
Question:
Assalamualikum i am confused by a hadith. i am not clear with the meaning although you have answerd to.someone before hadith is My ummah will nevr agree upon aberrance.whenever you see people are in dispute(Ikthlaaf) Follow the majority(ibn e maja 3940) is this hadees is regarding the sects or what kindly make it clear in light of commantry by the scholars.
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
cited it in his book Silsilat Al-Ahaadeeth Adh-Dha‘eefah wa Al-Mawdhoo‘ah, and he commented on it saying, “It is a very weak Hadeeth except for the first sentence as it is authentic."
Ibn Al-Qayyim explained the obligation of adhering to the Jamaa‘ah (the Muslim community at large); he underlined that the intended Jamaa‘ah in this context is the first community of Muslims, before people made changes and alterations in practicing the religion. It is what the Prophet, sallallaahu ‘alayhi wa sallam, and his Companions practiced. Whoever follows their path, then those are the Jamaa‘ah and the majority regardless of the large number of those who deviated from that path. He said: “Know that Al-Ijmaa' (consensus), Al-Hujjah (competent authority), and As-Sawaad Al-A‘tham (the overwhelming majority) refer to the true scholar who upholds and adheres to the Truth, even if he is alone while all the people on earth oppose him.”
He also cited a report about Ibn Mas’ood 
saying, “The majority of the people have left the Jamaa‘ah. Surely, the Jamaa‘ah is that which concurs with the obedience of Allaah.”
Hence, the number of adherents and followers is not the criterion here; the correct criterion is the adherence to the what is right, whether the number of the adherents is small or large. This is the correct criterion for labeling a Muslim sect or group as deviant or following the straight path of Islam and the right Jamaa‘ah.
Allaah Knows best.