The City playmaker scored twice, including a long-range thunderbolt in the second half, as the champions opened up a four-point lead at the Premier League summit with a stunning seventh successive victory on Tuesday.
Coming in his first league start since a spell out with coronavirus, De Bruyne stood out but the Belgian felt it was a team performance from which the whole side should take confidence.
De Bruyne said: “We started really well and I think we kept the ball at the right times, and once we saw the openings in the defence I think we attacked them really well. Then when you score the goals and punish them it gets really hard for them.
“It was a great game for us. A lot of players who didn’t play much in the last games played and they chipped in with goals. I think it is a big confidence boost for everybody.”
De Bruyne had a slow start to the season after a disrupted summer. The 30-year-old missed the start of Euro 2020 due to the facial injury he sustained during the Champions League final and then damaged ankle ligaments later in the tournament. He then suffered a further setback when he contracted Covid-19 last month.
De Bruyne said: “Obviously it has been a different season for me. I have had a lot of difficulties with head, ankle, Covid.
“There is nothing much I can do, these are moments that happen, but I came back and I am working hard to come back to the level that I need to be. I’m feeling better day by day, so I’m OK.”
It became apparent Leeds were in for a tough night from the early stages. Bernardo Silva had already missed a gilt-edged chance when Phil Foden opened the scoring after eight minutes.
Jack Grealish added a second shortly afterwards and De Bruyne made it 3-0 at the break. Riyad Mahrez scored a deflected fourth and Foden had another disallowed before De Bruyne made no mistake from distance. Defenders John Stones and Nathan Ake also got on the scoresheet.
“We punished them at the right times,” said De Bruyne. “It was still a very hard game physically and defensively they play almost man to man, but if you beat your man you have a chance of winning.
“The forward players, one-v-one, were amazing and that made the difference.”
It was an embarrassing night for Leeds with their veteran manager Marcelo Bielsa describing their display as the worst since he took charge in 2018.
Midfielder Stuart Dallas, who hit a post in a rare bright moment for the visitors, apologised for the performance.
“We’re devastated,” the Northern Ireland international told LUTV. “It’s not good enough from us. I can only apologise to the travelling fans and everyone who has paid hard-earned money to come and watch us.
“We got off to a bad start and it was difficult to get back into the game. Man City are a quality side but we shouldn’t be getting beaten 7-0. We knew what we were up against but there are no excuses.”