Ten Hag knew very well that in his first season he would not be able to win a trophy unless United were really lucky.
He and Manchester United are climbing up to a third position in Premier League but I agree that thinking of the trophy is too optimistic. A third or second position at the end can be great for them. Again we should remember that Ole Solskajer had a season with a runner-up position with Manchester United but after all he was sacked by them.
This should be an ongoing process without expecting any achievements in a season that has been filled with inconsistent team performances. I'm not going to forbid them from setting a target of becoming champions, but it takes time for a team that has just recently resurrected like Manchester United. I think it will be very hasty in its first season already targeting a trophy which at the beginning received the team in not good condition.