This
What is needed to be emphasised is the context of the time, of when he was the greatest. Football was more of a contact sport back then, compared to the football climate of today. Attacking players may have been protected back then, but not as much as they are today, not even close.
You could always have legitimate arguments of why either of Beckenbauer, Mattheus, Maradona, Pele, Zidane, Cristiano or Messi (and so forth, as the list continues..) are the greatest;
but what stands out for the players before Cristiano&Messi is that football was more of a contact sport, even as late as in the 90's. Even if you look at the classic battles between Arsenal and United in the befinning of the 21st century, you'll notice that we will probably never see a physical rivalry such as that ever again (which Henry also mentioned in the Premier League 25 anniversary segment).
Another important aspect to emphasise is that there were no galacticos or super teams back then. The football landscape was quite even across Europe. Dynamo Kiev could win a CL group with Real Madrid, and later also with Barcelona in it (when Shevshenko and Rebrov made their breakthrough in the lime light). Even IFK Gothenbourg won their Champions League group, ahead of Manchester United, Barcelona and Galatasaray, and were sometimes outsiders to go far. Rosenborg eliminated AC Milan from CL, and so forth. And Ronaldo, in a league that subscribed all kinds of European finals and trophies (Milan, Juventus, Lazio, Roma, Fiorentina, Parma..), stood out in the same manner Messi and Cristiano stands out today, except that Ronaldo's era had far more tough circumstances and competition.Imagine the likes of Cristiano, Messi, Neymar, in a team that does not contain 70% of ballon d'or competition, and yet having the pressure to perform and carry the team as they do. It still needs to be point out that both Messi and Cristiano are phenomenal, and definitely players to tell your grandchildren about, but I can't imagine them be as consistent as they are, in the older eras.
So...to be able to dance past defenders, in such pace, with that technique, with that vision, in a time were defenders had license to kick the sh*t out of you, and in a time when there were potentially ballon d'or winners in every rival team, as there were at least 5-6 domestical rivals, and lots more across Europe... That is why I will always rate players from older era higher than the stars of today, because I seriously doubt any of today's stars would be able to perform at their top in that era, with such intensity and consistency.