We've learned that it hasn't produced much research that holds up to replication, that the vast majority of research never gets properly replicated at all anyway, and that despite the endless meta-analysis of glorified internet surveys people's mental health hasn't been improving.
We're certainly learning how to use psychology to manipulate people though. Advertising, dark patterns, propaganda, and behavioral conditioning just wouldn't be the same without psychology research. We're performing research on children to learn the youngest age they can recognize a brand name (age 3 last I checked) or how best to keep them hooked playing a video game/child casino though and that research is making companies money hand over fist.
We're certainly learning how to use psychology to manipulate people though. Advertising, dark patterns, propaganda, and behavioral conditioning just wouldn't be the same without psychology research. We're performing research on children to learn the youngest age they can recognize a brand name (age 3 last I checked) or how best to keep them hooked playing a video game/child casino though and that research is making companies money hand over fist.