I think people mostly use it as a pretentious way to say “self reported experience” or “data from living people.” Things that are based on personal experience (

I think people mostly use it as a pretentious way to say “self reported experience” or “data from living people.” Things that are based on personal experience (anecdata) and perception rather than anything tangible. Which is important data to consider but often not very useful since perceptions are coloured by beliefs. Using case studies of personal experiences can also be biased towards more extreme experiences or perceptions that are outside the norm. I have heard of someone describing their “lived experience” of discrimination. They perceived discrimination in many situations where they had no evidence that the other party wasn’t impartial. But often the implication is that “lived experience” represents some form of truth that cannot be questioned.