That was totally one sided match and Manchester United football team played very well in this match and did 5 goals and that was excellent performance from that team . We expected that football team will win this match and they proved that they are able to be trusted and Fernandes and Casemiro were prominent players in this match because they did 2,2 goals in this match and played crutial role in win and Garnacho did second goal for his team and gave good start and after that we saw Manchester United team as a dominant team and Leicester City team could not escape from that .
This game prove to me somehow tht Ten Hag wasn't using this guys effectively even if I know they didn't play against a big team but their performance and drive in the game was totally different which showed that something really changed, the combination of having Fernandez at the front and casimero almost directly behind him became very productive as he got that support he needed in the right position that peaked his performance, this is another obvious point that due to players sentiment at some point, Ten Hag failed to place this players rightly which did affected their performance.
You are right, watching Manchester United game again Leicester City I noticed a little change in the performance of the team though they played against a weak team but they had this zeal to win the game and the way the players perform in the game shows that the former manager was not playing the players in their right position and that was part of the reason why the players were not performing well.