Ten Hag should be given support, he was a good coach before but what happened when he was at Manchester United destroyed everything, I think overall and it's not just Ten Hag who failed at Man United but several previous coaches did too so I still think that Ten Hag has good qualities like he did at Ajax so there is also a possibility that he can rise better with Leverkusen but the lack of management support makes it a bit difficult.
We all hope Ten Hag does well. The fact that United have struggled with several coaches who have been brought in other than Ten Hag proves that the problem is not only in the ability of the coach. But Ten Hag's challenge will actually start for the new season. If he does well, then the trust in him will increase and once again prove that he does have good ability. he may have to get full support from the existing team.