He was also responsible for Man United's failure last season because he was the head coach who had a much bigger role.
Although if you look at the players they have, they are also quite problematic because they are not able to play collectively together and cannot be responsible properly.
Since the Ferguson era ended, there has not been a coach with the best abilities who could bring Man United to great success. But Erik Ten Hak is still a good choice for next season.
This season there will be big changes that will be made by Man United because they have changed several coaching staff and management and we hope it will be a good start.
Man United's failure last season was not entirely Erik ten Hag's fault because many players were injured, making it difficult for the coach to implement strategies. The proof is, when the players started to recover, they managed to get the FA Cup at the end of the season. So it is very natural that Erik Ten Hag is given another chance, especially as you said, several Man United staff have been replaced, of course this will be a good start for next season.
Because on the other hand, I still can't tell whether Ten Hag is bad at tactics or the player has no tactical intelligence at all. Most diplomatic answers will fall somewhere in between. However, I believe Ten Hag is a tactically astute coach with a proven track record from when he coached Ajax. Although Man United's failure is of course also caused by their players, they have a proven track record of frustrating the three previous managers and the current Erik Ten Hag.
However, with the opportunity that Man United has given Erik Ten Hag, I hope that Man United can become a strong team and be liked by their opponents next season.