The World Cup is the World Cup. No other ODI tournament counts. If you win it, you should automatically be number one in the ODI rankings, which should reset after each WC.
Seriously, who cares about any other ODI series but this? It's that important. So, if you win it, you deserve massive kudos because you've been the best team when it's mattered. Saying team X or Y didn't deserve to win a WC is bollocks. They did what they had to do when they had to do it. Sure teams like SL in 96 and Pakistan in 92 peaked for three weeks, but that's the game ffs. I mean, SA were the best side going into the 99 WC, Australia was terrible during the early stages and managed to drag their way into the Super Sixes before getting on a run. Likewise, the England 05 team got on a roll with their mint eating proclivities to win the Ashes against a far superior Australian side. They weren't fit to carry that Australian team's jockstraps, but they won when they had to. That's sport ffs.
That's what tourneys are about. Teams can win however many football friendlies or however many ODI series in between WCs (or in football, The Euros). No one remembers them. All that gets remembered is World Cups.