Here is how Wikipedia describes the process of ranking the “NFL Top 100” list every year:
The NFL Top 100 is an annual list that features the top one hundred players in the National Football League (NFL), as chosen by fellow NFL players. The rankings are based on an off-season poll organized by the NFL, whereby players vote on their peers based on their performance for the recent NFL season. Only players that are not retired in the next season are eligible for consideration.
So we are clear, the list is a broad representation of how NFL players feel about the value and talent of their peers.