True. The Buddha said there were many things he was aware of but taught only a little of it, necessary for the trainee to progress on the path. If he taught this there must be a reason. Maybe to identify incidents of true realisation?
There is some overlap initially. For example understanding the cause of suffering (as in the Dependant Origination) or causality can lead to a understanding of anatta, which is a deepening of the understanding suffering (Dukkha). However when the practice reaches culmination in Stream entry the ‘rapid succession’ results.
The Four are distinct in that watching phenomena arising and passing away (Sankhara dukkha) is the deepest practice in the first truth. This can be quite difficult practice.
Seeing causality, impermanence, unsatisfactoriness (nibbida, viraga, nirodha SN22.59) and not-self (anatta) would be the practice in insight (vijja) leading up to the second Noble Truth.
The arising of the Dhamma eye would be the 3rd Noble Truth and so on.
I appreciate that it is not linear. However it’s useful to explore some of these less well known teachings as well.
With metta