That expressed my interest in Network marketing organization and I went through this paper from Kellogg school https://www.kellogg.northwestern.edu/faculty/coughlan/htm/personalpage_files/Papers/Coughlan%20Grayson%20IJRM%201998%20article.pdf
IMO such business are totally fine if you enjoy routine job. Seems like the friend was inspired by some fancy youtube or insta blogger. But I feel that he underestimate the high returns of such business as most of MLM are focus on the shiny side only. The only advantage of such business is experience in retail sales that can be useful for further venture.
So, should I try to convince him to exit this MLM business and how can I reinforce my arguments?