Brzenk is one of the GOATs (if not the GOAT) regardless of the sport. Very few, if any, people have been at the top for as many decades as John Brzenk has.
Was Brzenk actually the #1 world arm-wrestler for 30 YEARS?
Did he win the outright world championships in years between 1985 to 2015? Or thereabouts?
If so, that would have to make him
the GOAT, regardless of sport.
Who else has done that in any sport?
Even Floyd Mayweather wasn't #1 for that long.
I can't think of anyone who was #1 for that many years/decades.