To me it's that word legend again. Every moment of Mahrez's csreer in this country, has been shown on tv and, as such, there's no mystery to him.
Weller probably played in tv games no more than 20 times and in many of those csses, brief highlights,. Add to that, due to the hooliganism of the time, crowds were about 10k so all you've got to work on is fading memories of 50+ year olds.
Weller was a wonderful character with wonderful ability on dodgy pitches, Mahrez is a better footballer, no question.