As reported in this science article X Marks the spot Centre of Milky Way, a X shaped feature is confirmed centered on our galaxy's centre, when looking on from within the plane of the Milky Way.
In terms of the presented explanation of this feature in this article, I would think the X shape could also be explained by historical influence on star formation, and to a degree star type, of polar outflowing material from the central galactic black hole.
At least assuming, if it were true, that its rotational axis over the eons of growth has varied about the axis perpendicular to the plain of the Milky Way. I am suggesting a precession type movement over its lifetime, rather like that of earths rotational axis. The orientation of its rotational axis impacted by large mass inflows at various ties, in particular early in its life when in falling mass to black hole total mass ratio was lesser than present times.
I would think there would also be likely some gravitational interaction, like wobble, of the inner swirling mass of the interstellar material within the galactic plane as the mass of the central black hole increases non-uniformally with episodes of in-falling material, such as during earlier galaxy mergers as part of our galaxies formation process.
Outflow of material from the black hole, high energy particles of mass and radiation, would from my understanding have influence on stellar formation from changing the characteristics of the interstellar material from which the stars are later formed, as well as the effects of compression of material triggering gravitational collapse for star formation.
In terms of a precession type movement of a rotational body within a medium, the X shape seems so distinctly characteristic. It seems to be a self evident logical possible explanation to consider. At least from a non-professional and intuitive point of view! Yet such is not mentioned as explanation in the article.
Why should such a model be excluded as explanation for this X feature?