In this case, I will be very surprised if:
a) You are able to finish the mesh in reasonable time (few minutes).
b) Mesh will have only 3.7ish million elements
As you claim, a is false (as expected) and b is true, then this is strange and probably this question is for developers to answer.
In your first post you mentioned 90 million elements in your earlier try. In latter trials the count was 3.7 million. So there appears an uncertainty in the trend.
I maintain that you start from a coarse mesh and go from there, so that at least you rule out the unreasonably fine mesh.
Auto mesh number of elements are usually accurate but they don't result in smooth meshes even after multiple adaptations. And whatever manual mesh sizing that I do, the ram gets used far too much except for extremely coarse mesh. You can see that the CPUs are all idle.