Our every action in the real world leaves a smudge of data in the Metaverse, stored long after our death, and if mediums have a long tradition, chatbots had the distinct advantage of the unmediated talk.
It was pointless for computer scientists to explain that it was no sort of "uploading" of a person; you could as well say that somebody was possessed by Arthur Conan Doyle because they were writing a Sherlock Holmes pastiche, or that the spirits of dead presidents are hosted inside a temple in Disney World. Who, able to chat with a lost loved one as they had in the past and recognize their quirks and in-jokes, would worry about philosophical arguments and technical details, or consider the frequent glitches as anything more than proof than the miracle was real
Whatever it did for the soul of the departed, the Echoes saved the old social media platforms; they had long ceased to be attractive, but owning the words and rights of the spirits of family, friends, and lovers made retention rates phenomenal. There was serious money in Necromancy by NLP - too much to worry about the concerns of psychologists, the bulls, fatwas, and dead threats, or the slowly rising numbers of hopeful suicides spurred by sleepless influencers of immortal enthusiasm.