He let Antony play just after the player was back to the team training and we knew the fans were still against him.
Also, we saw Sancho near Carrington training in Manchester United maybe even this payer will get back to Manchester United and this shows any palyer can have any behavior but in the end they can still play there which is not good for Ten Hag and his team.
I wouldn't take into account the fans too much whether I let a player play or not. If a manager were to do that, what would be with all those players that weren't welcome when they newly joined a club? Let them sit on the bench only because the fans have a problem with the player? That is not a viable approach for any manager ever.
But Ten Hag making wrong decisions is the problem or maybe his training isn't good. I don't think that he lets the wrong players play all the time, but they don't perform well, which is more indicative of problems during the trainings.