@leafybye Picking up where we left off on the observation, you are correct when you say that a monograph is a comprehensive worldwide treatment for a taxon. And although many revisions have since been made to the Ribes monograph, none of them have been significant enough to really warrant the title of "monograph" (although the definition of that term is somewhat arbitrary).

The other thing you ask, about when R. indecorum was 'upgraded to species status after 1970,' is a little trickier to answer. As far as I can tell, Ribes indecorum was first described in 1902 in this scientific journal. Then in 1907, the species Ribes indecorum was synonymized with the new variety Ribes malvaceum var. indecorum in the aforementioned monograph; but, one year later in 1908, the Flora of North America treated this new variety as a synonym of the species Ribes indecorum! I think that the misconception you have is that something can be unilaterally 'upgraded' to a species in some sort of objective sense, when in reality there is no objective universal source for which name is 'correct' and it has always depended on which author you choose to recognize as correct.

So Ribes indecorum was never 'upgraded' to a species some time after your old San Luis Obispo was published, it is simply just that the old San Luis Obispo decided to use the monograph's treatment of the species, while the vast majority of other sources (including iNat and the big online checklists like POWO) decided to use the FNA treatment.

To be fair, something to keep in mind is that the author of the monograph was a Polish botanist who (as far as I know) did not do very much field work in North America, so he was probably describing R. malvaceum var. indecorum solely using herbarium sheets, which could certainly lead to error.

I am still not sure that I interpreted your question correctly so if you are still confused just let me know and I'll get back to you.

@clabsauce I think you did answer my question. Also when you said, "when in reality there is no objective universal source for which name is 'correct' and it has always depended on which author you choose to recognize as correct." I guess I have noticed different botanists/taxonomists recognize different scholarly works to decide what a Genus is comprised of. I assumed incorrectly that there might have been some consensus about Ribes in 1970. I think I would need to read all of the relevant papers from 1902 to 2007 to see what the arguments were for R. indecorum as a species. Again, I realize species, subspecies, and variety are subjective and even nuclear analysis has its limits, but data using the modern tools can help make a better argument for certain taxonomy based on systematic botany. If I understand the field correctly, that is.

Also we as people trying to categorize life can recognize that certain plants look different than others, but might not always be justified as being a variety, but could be a form, or phenotype. Science is used to try to classify life, although imperfectly. I suppose only recently we gained the tools to do DNA / nuclear analysis. It is a lot to digest, but even https://en.wikipedia.org/wiki/Molecular_phylogenetics
has limitations.