This is survivor bias; SS keeps some beginners engaged but there's no count of those who drop off or never start it. I was in the latter group; it was the first program recommended to me, but I was leery of it because I don't have medical insurance and was skeptical about the feasibility of the suggestions based on what I knew about my own body, so I just did nothing about it. When I did start lifting, I started out with light weights and spent months figuring out a program while getting a kinetic understanding of the different muscle groups and how they worked together, spamming volume for a while and gradually adding more weight.

I don't mean that SS is a bad program, it works for lots of people and it's very accessible. But I also think it's way oversold and not magic.