Liverpool didn't expect their match with Manchester United at Anfield would end as a draw match because of Manchester United's low performance this season, and they won Manchester United heavily last season at Anfield.
Manchester United knew that if they came out to attack in that game they were going to lose, thus Ten Hag had to respect Liverpool and set up to defend for most of the game. It was not a bad result for both sides, but Liverpool would be the more disappointing of the two teams, United would be happy with the one point.
Arsenal are back on the summit, five points above the defending champions Manchester City; both Liverpool and Arsenal would know that they cannot write City off and if they want to have a chance of winning the league, they have to pull clear of the City now that they are wobbling. City are still very much in the title race and they remain my favorite candidate for the EPL title.
That is football for you. When you meet a stronger opponent you have to play them with tactics that will help you win the match or go home with a point. Manchester United did not play defensive football all through the second half, which was why Manchester United was able to get a draw at Anfield. Also, Manchester United had an opportunity to take the lead against Liverpool, but Garnacho failed to score.