Many doubt Ten Hag and not only that, Leverkusen's management also does not support by bringing in many quality players so we can see that overall Bayern Munich's strength is much better than Leverkusen so I think realistically that Leverkusen will not be able to put fierce pressure on Bayern Munich for the Bundesliga title.
Many doubting Ten Hag was supposed to be a fueling pressure for him to want to do better but he still do not look like he even cares about that and this is not about the Management of Leverkusen, there are other coaches out there who are putting it to the Management of teams that they need a certain kind of players if they must produce the results expected of them and the Management has got to work with these coaches on this even when they are financially constrained, they still have to find a way around it.
I think Erik Ten Hag doesn't want to pressure Bayer Leverkusen management that he needs some certain kind of players because if he fails to perform well at Bayer Leverkusen, he will use it as an excuse and blame Bayer Leverkusen management for not giving him the players he wants, just the way he blamed Manchester United management for his failure at Manchester United.