Messi fulfilled a lifelong dream when he captained Albiceleste to their third global triumph and their first since 1986.
The 38-year-old, who now plays for Inter Miami in America's Major League Soccer, saw off Van Gaal's Netherlands side in a bad-tempered quarter final clash before eliminating Croatia in the semi-finals and defeating France on penalties in the final following an energy-sapping 3-3 draw after extra time.
Van Gaal has since stepped down as Netherlands manager and has been replaced by Ronald Koeman.
Speaking at the Eredivisie awards to Dutch outlet NOS on Monday, Van Gaal said: “I don’t really want to say much about it.
“When you see how Argentina gets the goals and how we get the goals, and how some Argentina players overstepped the mark and were not punished, then I think it all premeditated game.
“I mean everything I say,” he continued. “That Messi should become world champion? I think so, yes.”
