Is our universe trapped inside a black hole? This JWS Telescope discovery

This newsblog takes one piece of the paper [1] and blows it up like it's the most obvious thing ever and completely hand-waves away the alternative, while the paper itself actually provides some compelling evidence for the alternative explanation: This asymmetry is because of our own galaxy's rotation. It would be an insane coincidence to have the large scale structure of our universe be more asymmetric towards the poles of our galactic plane and the further you go away from our galaxy (especially when velocity blue shifts would obviously make one type of rotation for galaxies more visible in the high-z regime where JWST primarily looked). Forget black hole cosmology, if you believe what this article suggests, then special relativity itself may be wrong. The data is pretty sound and perfectly in line with earlier observations that found no asymmetry if you believe our own galaxy's rotation is the culprit. So if I had to bet, I'd say we misunderstood galaxies and not the universe as a whole. Mostly because galactic physics is incredibly complicated and has very whimsical empirics, whereas we have some really solid theories and data on the universe as a whole.

[1] https://academic.oup.com/mnras/article/538/1/76/8019798

Thanks for link. Amazing work. I'm less than noob, so barely comprehend this topic, much less this paper.

ELI5: Per "5.2 Physics of Galaxy Rotation", could the Milky Way's relative movement, in addition to its spin, also effect the observed assymetry? In Figure 10, is the Milky Way also moving toward the blue and away from the red?

Thanks for humouring my question. Everything about astronomy and JWST just blows my mind. Like how Figure 10 sorta resembles yinyang. What a time to be alive.