In the Kali age people tend to be greedy, ill-behaved and merciless, and they fight one another without good reason. Unfortunate and obsessed with material desires, the people of Kali-yuga are almost all śūdras and barbarians.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
तस्मिन् लुब्धा दुराचारा निर्दयाः शुष्कवैरिणः । दुर्भगा भूरितर्षाश्च शूद्रदाशोत्तराः प्रजाः
tasmin lubdhā durācārā nirdayāḥ śuṣkavairiṇaḥ | durbhagā bhūritarṣāśca śūdradāśottarāḥ prajāḥ
SB 12.3.25