Are you saying that by getting third place in the standings, Ajax will play in the Champions League next season? From what I know, the Eredivise only gets 2 slots in the Champions League every season and those are first and second place. In fact, the previous season they only got 1 Champions League ticket and that was Feyenoord. You can see PSV, which was in second place last season, playing in the European league. So I agree with you that Ajax was able to get third place and that means Ajax will get a ticket to play in the European league, not the Champions League. Correct me if I'm wrong.
Ajax have not been at their best performances but they've definitely been winning games and have been consistent to it. Definitely a coach has his own impact in a team, once the head is faulty, there'll always be loopholes. It means a lot for a team to get victorious consecutively in a row and for Ajax, that's caused a gradual improvement regardless not doubting that they still have to put in more work. They've got players no doubt but the squad needs to be better.
Ajax is a team better than a narrow win, at the moment though, finding the right player who's top and ready in all areas to give that competitive capacity in both the domestic league and the European leagues will be hard. Their inconsistency is unhealthy and they just have to find a way to stop the losses from occuring through a narrow means. There's still a bit of time for their errors to be reshaped and corrected too.