Brown is currently 5th all-time in career punt returning yards. No one else in the top ten is ranked statistically in the top ten in any other meaningful statistic. Brown is the only player in NFL history to be ranked in the top ten in every meaningful statistic for his position in addition to a position reserved for specialists.
For comparison....Deon Sanders, who was elected to the HoF partially for his punt return skills (and partially for his mouth), currently sits 28th all time in punt return yardage. ...and old Neon Deon never met a tackle he didn't avoid.