Well the redshift = distance assumption is directly tied to the big bang and expansion. I simply disagree, It has been falsified ...
Things aren't that simple here and more needs to be done to be a falsification. Perhaps you missed this part?
An argument for intrinsic redshift is particular interesting to the extent that it applies only to one class of objects (quasars) or perhaps a few others (such as tighly clustered galaxies), because it does not call into question the more general Cepheid and Ia supernova measurements which have independent corroboration. It simply suggests that one small class of objects, which were outlier data to start with, are at different distances than existing models would predict. Unlike Cepheids and Ia supernovas we don't have, e.g., good calibrating data on what a quasar should look like up close.
This doesn't have to have a huge amount of impact on Hubble's constant [related to expansion rate], because Hubble's constant data flow from a variety of redshifted objects.
Anyhow, here's my take on what needs to be done if we're really going to do this in a scientifically honest way.
(1) Distance determination and age determination is a thorny business in astrophysics. Historically accurate measurements typically come from several trials/measurements, typically over much time. Indeed, very rough estimates that weren't very convincing have been improved upon over decades and converged upon values that agree with BBT. So, if an anomaly is going to upturn all of cosmology, it needs to be followed up to be sure the values are accurate enough. From what I have read, there are things that can be done to give more confidence to the distances involved with anomaly NGC 7603, etc. and the mainstream is just as much at fault that this hasn't been done. We need to also keep in mind that for ones where this has been done, like Stephen's Quintet, things checked out with BBT. (Instead of calling the results flimsy here, we need to show why the Surface Brightness Fluctuation distance determination method used here is not sufficient, using math not appearances)
(2) Regardless, (1) would still not qualify as a falsification for the reasons stated above in the quote - applies only to a small class of objects and determination of the Hubble Constant not dependent upon (1) alone. In addition, we would need to show how and why the
physics behind Cepheid Variables and Type IA supernova is incorrect. Even more, the redshifts measurements in this much larger class of objects is in agreement with these "incorrect" physics. So, we would need to somehow explain this, since the two corroborate each other and offer greater support to the BBT combined than do the quasar measurements.
(3) We would need to explain why all the effects I mentioned above, like the Sunyaev-Zel'dovich effect, Integrated Sachs-Wolfe effect, Unique CMB signatures, Gravitational Lensing (and the ones I missed), which are also backed up my powerful studies, are also somehow wrong. These provide powerful evidence for Big Bang, which would need to be countered. You don't just drop multiple solid empirical observations that support something, because you find one solid empirical observation that doesn't. The discrepancy needs to be accounted for.
(1), (2) and (3) combined would provide a convincing argument for BBT falsification, where we would would then run into the next related set of problems.
(4) If we're going to somehow replace BBT with some alternative theory, this theory needs to explain all verified post-Newtonian phenomenon better than General Relativity overall across the board, including Perihelion Shift of Mercury, Deflection of light by the sun, gravitational redshift, declining orbit periods, frame dragging, gravitational lensing, radar echo delay, etc. This is analogous to coming up with a better alternative to F=ma, like I mentioned above.
(5) More crucially, it would have to come up with it's own estimate of the Universe's mass-energy content and explain why despite reproducing all the physics in (4) the Universe would not not have arisen out of a Big-Bang-like condition. If it falls within the region on the plot I mentioned above, I would think this is going to be really tough to do.
(6) I won't even mention the problems with QFT predictions!
That's to start, but this list would get a lot longer. Also, more specific problems would arise depending upon the form of the alternative theory too. Some of these problems would be shared by current theories, but any alternative theory would need to offer better explanations to be compelling.
Anyhow, this would be the responsible way of doing things here. You can probably tell I would I have been reading Stephen Meyer lately, but in the spirit of his books, this is what would need to be done for the BBT to be truly falsified and to have a competing alternative theory/hypothesis that truly offers "superior explanatory power" across all observations.
I'll probably be heading back to work this afternoon (feeling better) and will be gone the next few weekends, so any more replies to this thread will probably be few and far in between.