Why don't all Muslims follow the Salafi methodology?

A Muslim will not attain salvation except by adhering to the Sharia of Allah Almighty according to the understanding of the Salaf of the Ummah. The Companions, may Allah be pleased with them, are the ones who understood the religion that Allah approved for His servants, just as Allah promised those who believed and did righteous deeds succession, empowerment, and security. The majority of the Ummah and its great multitude follow the Ahlus-Sunnah wal-Jama'ah.