The Dutchman was widely criticised for his relatively dour approach at United, with the club enduring a run that saw them win just four matches out of 16.
Van Gaal was eventually sacked in May 2016, to be replaced by Jose Mourinho, but he has now insisted that he wanted to have United playing as City do now.
Indeed, Guardiola's men need only win their next two games to win the Premier League title, having amassed 81 points from 30 games.
"Pep Guardiola is, for me, currently the best coach of the Premier League," Van Gaal told SportBild. "Pep made City a machine.
"He shows a football that I would have liked to play at Manchester United. But he has better players for it. For me, the process would have taken longer. Unfortunately, I did not get the time."
Van Gaal has also rubbished any suggestion that he holds ill will towards his successor at United, maintaining that it is unsurprising that top managers want to sit in the Old Trafford dugout.
He has, however, taken a swipe at the club's executive vice-chairman Ed Woodward, whom he believes reneged on verbal promises despite United's FA Cup triumph.
"I am not disappointed with Jose Mourinho. Every coach wants to train Manchester United, it's one of the biggest clubs in the world," he added.
"I think Jose wanted that, too, and although he was able to do so in 13th place, he had a chance on a fantastic team like Chelsea. I was in fourth place! I still do not blame him.
"What I find wrong is when a CEO says we're totally happy with you, do not believe the press. Then you win the FA Cup and still be fired."