The argument is that we should not expect theology to make sense because some buts of science don't make sense: e.g some aspects of advanced physics are strictly incomprehensible - don't add up - are incoherent. Yet they seem to be true...
So why can't Christian theology be just as nonsensical as science - like many statements of the nature of the Holy Trinity - and just as true as science?
My answer is that the paradoxical theoretical physics is not so much true as useful - scientists seem to be able to make use of them in prediction and manipulation. But theoretical physics for the past many decades has been trying to make sense of, and get rid of, these paradoxes and incompatibilities (e.g. the incommensurability of general relativity and quantum theory) - so clearly they are not regarded as true in the sense of representing ultimate reality.
But with theology we seek truth in the sense of ultimate reality.
More importantly, Christianity is about a loving personal relationship with God - a Father and Son relationship, a fraternal relationship.
Thus the analogy with science breaks down. In science things may be useable even when they do not make sense: but they are not about entering into a personal relationship with the constituent parts (photons and quarks...).
How can we have a personal and loving relationship with God (which a Christian must do - it is the primary commandment) when God is neither one nor three persons, yet is also both one and three persons?
This is either a God of incomprehensible abstraction, or else an impossibility altogether.
This kind of paradoxical Trinitarianism can be a major stumbling block - indeed a roadblock - to faith for anyone who takes it too seriously.
And it is missing the point spectacularly. The Trinity are personages, that is what is most important. They always love each other wholly and always work in complete harmony.
That suffices - why sabotage the personal relationship with God and Jesus Christ and the Holy Ghost with paradoxical philosophy?
And having done so, for reasons which may have been compelling in the fifth century AD - why elevate this paradoxical philosophy to become a dogma and definition of Christianity?