There are some theologians today that want us to reject the idea of divine simplicity as untenable.
For myself, I think it’s a necessary concept that explains the nature of God - related to His unity or oneness and perfection of being.
However, in many areas, it seems that when we describe God we violate the idea of simplicity. We speak of attributes. Plus, we have the created world. Finally, there is the Trinity of Persons.
The only way I can reconcile all of this is with a simplistic view – that the human mind, using a scientific approach, is always reductionist. For us to explain anything, we categorize and compartmentalize.
This makes it impossible for human beings to describe God accurately. We will speak of energies as distinct from essence. And it is even a problem to talk about essence, nature and power, for example as not being parts of a whole.
We end up with the same, and more difficult problem with Father, Son and Holy Spirit being one in a divine simplicity.
So, I don’t know exactly what theology you’re referring to here, but it’s my guess that nobody can reconcile these things, East or West, in a formula that is purely logical and non-paradoxical.
For me, divine simplicity is a truth that explains some things when taken on its own - as it speaks of wholeness.