When a new theory supplants an old one, it is usually for a good reason.
The practical issue is that we have yet to find an instance where the current theory of gravitation gives an incorrect result. Hence, there is no basis for "vortex" gravitation (or any other theory) to replace it...... for the moment.
I have a great deal of trouble with Hoagland's stuff; latching onto the "Face on Mars" hysteria, combined with all his conspiratorial speculation he's into, really makes him sound like a lunatic rather than a serious scientist, which he once was.
I don't know if he was ever a scientist. He was certainly a science journalist and planetarium manager. He was very good, too. A scientist? No, not formally. But perhaps in spirit.
The Face on Mars is a joke, not for the purpose of having fun and playing with the gullible, but for encouraging people, meaning Congress and NASA, to let us all share in the exploration of our solar system.
Hoagland's subspace or hyperspace physics, or whatever title he gives it, is not his, he is the journalist. Although the mathematics of the day was not up to the task of dealing with the idea, it may come back, probably in an altered form suitable for computer modelling. Along those lines stay tuned for developments of the fifth dimension out of Princeton and watch for Nima Arkani-Hamed, who may have something to say later.