The well-received question in Astronomy SE What is the maximum transmission distance of the radio signal in the outer space which could still be understood? was asked in November of 2013 and so is way too old to migrate, but I think that it could receive some good answers here and would be of specific interest.
If asked today, I think it would be quickly migrated from Astronomy to here.
As far as I can tell we haven't explored the "maximum distance" for radio yet, especially to the level of detail asked about in the question; additional issues are mentioned besides path loss.
Since the time of posting, the Breakthrough Starshot initiative has been announced, and so the topic of very long distance communications has a renewed interest.
The question may need a little refinement, but I think it would do well here.
Question: Would it be okay if I re-ask this Space Exploration-related question from Astronomy SE here considering that it is six years old and therefore too old to migrate?