If the original commenter has an issue with this, wait 'til they find out about modern CT scans. Or hell even JPEGs.
To quote from a paper[1] on the history of CT scanning:
"Initial images were of inert objects, then specimens from an abattoir, including bullocks brains and pigs bodies"
or
"The prototype was installed at Atkinson Morley’s Hospital in South London where the first patient, a middle aged lady with a suspected frontal lobe tumour, was scanned on 1st October 1971. The surgeon who operated on her shortly afterwards reported that ‘‘it looks exactly like the picture’’"
The default scientific approach to a new imaging algorithm, and especially a new implementation, it to try it on a simple well understood examples first.
[1] Beckmann, E. C. (2006). CT scanning the early days. https://www.birpublications.org/doi/10.1259/bjr/29444122
Rather than attempt to disentangle, large physics collaborations normally have a “You are on all papers we publish while here and X years after you leave”.
It depends very much on the field of research and the paper in question. In some fields, it's very common to list the names of the authors alphabetically, no matter the size of their contribution.
https://iopscience.iop.org/article/10.3847/2041-8213/ac6615
>"Since the interferometric measurements are often incomplete in the Fourier domain, the inverse problem of reconstructing an image from the observed data set is usually underdetermined. Consequently, the image reconstruction requires prior information, assumptions, or constraints to derive a reasonable image from the infinite number of possibilities that can explain the measurements."
They seem to have gone to great lengths to address this issue, however. Multiple imaging approaches, synthetic data tests, etc.
https://iopscience.iop.org/article/10.3847/2041-8213/ab0e85/...
Why would looking at something that isn't a supermassive black hole at the center of a galaxy prove that this approach works or doesn't work? You'd have different constraints to apply. See for example VLBI measurements of quasars, which seem to employ the same kind of imaging approach. Theoretical models of quasars aren't the same as theoretical models of black holes. They seem to be using these theoretical models as constraints on data interpretation. Unless the theory is completely wrong, which seems unlikely, this looks like a valid approach.
https://arxiv.org/pdf/1701.04760.pdf