This is a simple form you can reuse: Does [increased polarisation of views] increase engagement? [Yes] Therefore, we can conclude that Facebook does this. FB

This is a simple form you can reuse: Does [increased polarisation of views] increase engagement? [Yes] Therefore, we can conclude that Facebook does this. FB is designed for maximum-engagement regardless of whether that is positive or negative for the useds (to use Richard Stallman's pun).