Inasmuch as I don't rate Erik ten Hag among the best managers in English Premier League, I wouldn't not agree to your opinion that he's the worst manager in the universe. That's exaggeration at it's peak and you know that. We saw how Dutch club Ajax was performing under Erik ten Hag and for him to also manage to win two trophies in two seasons for Manchester United makes your description of him absolutely unfair. I'm not satisfied with his performance with Manchester United because considering the quality of players at his disposal, I expect much better than I've seen from him. He's a good manager for average European clubs but not for a big club like Manchester United.
At Ajax he did quite well and that's not in dispute and he was given the accolade for that but on a world class scale, a coach should be able to literally fit in to almost any place and still produce results, when his productively is been restricted with space time and probably location, then he's still got some work to don on his career in other to be at the world class level. At Manchester United ten hag has failed to be at his very best such that he can be portrayed on that light of good he was seen at Ajax but he's still not so terrible to fit in the description of the other poster.