https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5459228/
https://www.bbvaopenmind.com/en/science/research/psychoanaly...
https://link.springer.com/referenceworkentry/10.1007/978-94-...
https://www.skeptic.org.uk/2021/07/psychoanalysis-science-or...
https://philarchive.org/archive/FERIPA-6
That quote you included seems a little funny. It’s not making any direct or compelling argument in favor of psychoanalysis being science, it’s just saying well if psychoanalysis isn’t science then other disciplines aren’t science either, and since that’s sometimes not true, then Popper is wrong. It’s a slippery argument with some assumptions and big holes, and perhaps most glaringly it is intentionally ignoring the magnitude or degree of scientific experimentation, and attempting to frame the issue as only binary: science or not science.
I’m sure there is some modern psychoanalysis that is scientific, but OTOH it seems like the foundations of psychoanalysis, especially Freud, are certainly problematic from the perspective of science, right? Psychoanalysis has a valid, earned reputation that may take a very long time to fix, even if today’s practitioners are being careful and scientific. This could be compared to chiropractic medicine - some of it is valid medicine today, but it definitely came from non-medical, non-scientific origins.
There appear to be at least 2 separate arguments going. One is whether psychoanalysis can be a science, and the other is whether it actually was a science historically. This is why both sides are somewhat right: proponents of psychoanalysis argue that it can be scientific, which is true, and opponents argue that it wasn’t scientific in origin and has a troubled past, which is also true.