Can you kindly stop spreading misinformation.
Brahmins are those who choose take up the study of scripture and renounce wealth, land and weapons.
Kshatriya are those who choose take up weapons but renounce wealth, land and scriptures.
Vaishya are those who choose take up wealth and renounce land, weapons and scriptures
Sudra are those who choose to take up land (farming, cows) and renounce trading, weapons and scriptures.
They are not categorised by their work, but by their "guna" or Nature.
Like all system, they too failed when the checks and Balance failed with changing times and hostile environment.
If a person born a shudra learns the scriptures and does pooja in mandirs then he is no more a shudra, he is a Brahmin.