His psychosis allowed him to see reality as being extremely flexible and influenced by often malignant forces. That applies to modern society as more of our "reality" depends on things such as social media and that's clearly able to be influenced by bad actors. It's only going to get worse as we can't believe that a picture or video of someone isn't faked and so all we can do is try to figure out our own narrative.

His work also features lots of surveillance themes (again, likely due to the nature of his psychosis) and I can't think of anything more relevant to modern society. We've now reached the stage of technology where it's feasible for us all to be living in a panopticon.

Another major theme in PKD's work is "what makes us human" and we're getting close to producing LLMs that seem to behave as though they are human. If we give an AI a sense of personal identity with some fake memories, then would we be able to tell that they weren't human and what would they "think" about it?