Surely World Cup is probably the most important competition to be won, but it’s not everything. Pogba won the WC as key player for France, but he doesn’t gain much respect from the fans, Klose is the all time top scorer and won one for Germany too, but he wasn’t being discussed much and wasn’t consider anywhere near the best at any point of his career. Cruyff, Di Stéfano, Puskás, Best, Platini, Eusébio have never won any WC, with some of them rarely feature in any of WC matches, yet they are all widely regarded as one of GOAT for long time. I just felt, for most players, they could only feature in less than 10-20 WC games throughout their career, but at club football they usually feature over 500-900 games, surely being GOAT in over 500-900 games are more significance (or at least equal) than being GOAT on 10-20 WC games. (But the player is GOAT in both, then he will be definitely regarded as GOAT anyway)
Another thing is media coverage of football matches has changed drastically over time. In the old days world population could only watch WC, and couldn’t get access to most of the domestics league games or cup competitions. Nowadays any top leagues and CL are watched but hundreds of millions, so people tend to value those matches/competition more. In today’s world, the most prestigious and highest quality competition is CL, and with its global media coverage is also another significance factor. Being great on it will definitely be decisive factor on how the world would view on the players. Examples are Ballon D’or usually will be given to best performer in CL.