I remember that analogous findings have been made for spin directions of distant stars but now distances are indeed enormous, larger than the length scale .1 billion years for the large voids. Also the stars are aligned along lines.
TGD explanation is one of the oldest pieces of TGD inspired cosmology and was originally proposed as an explanation for why galaxies are arranged like pearls in necklace. Key players in the model are of course cosmic strings thickened to flux tubes during cosmic evolution so that their magnetic fields and energy densities reduced. Living matter would be full of them! This would be the new element needed to explain the findings.
The cosmic strings preceded the visible matter resulting in their partial decay when space-time in the usual sense formed from the soup of cosmic strings (string-like 4-D surfaces with only 2 big dimensions). String gas condensed to form space-time (analog of inflationary period) and radiation dominated cosmology emerged. Elementary particles emerged as energy of cosmic string. In inflation theory they are believed to emerge from inflation fields for which there is however no support.
Expanding cosmic strings would be still there ands since they carry topological monopole fluxes (made possible by CP2 geometry) give rise to magnetic fields in all scales without need for currents to create them: the existence of these magnetic fields is a mystery in standard cosmology. Their magnetic energy is the mysterious dark energy and their description in TGD framework requires small cosmological constant. Also galactic dark matter could be mostly dark magnetic energy assignable to the galactic dark string going through the galaxy: this explains elegantly the constant velocity spectrum of distant stars in galactic plane.
Quasars and also other matter in scale of billions of light years results as decay products of cosmic strings and quasars formed kind of pearls in necklaces defined by cosmic strings. The interactions of primordial quasars with cosmic strings and each other at time when they were near to each other implies strong correlations between spins of these objects. The main deviation from standard cosmology is that the seeds of stars existed already during transition to radiation dominated era.
The parallel spins of quasars could originate from that of cosmic string. The simplest cosmic string is at rest in comoving coordinates (Robertson-Walker coordinates) and is parallel to x axis as one goes to plus/minus infinity but has kink near origin (sigma curve) (see this). In local Minkowski coordinates it appears to be differentially rotating since cosmic radial coordinate r is expressible as r= rM/a, a the cosmic time, and therefore depends on time since angle coordinate Φ along string is function of r and thus of rM/a, and therefore of cosmic time.
The quasars could be generated in the region in two strings have made a close encounter: the center of Milky Way gives support for this. The angular momentum and energy lost by cosmic string goes to the quasars and they start to spin in the same direction as cosmic strin rotates locally. Analogous mechanism could explain why planets tend to rotate in same direction.