Slay traveled from 1980s ballroom culture through Beyoncé's "Formation" into universal vocabulary. As praise it is simple: slaying is succeeding with style. The "slay count" in a conversation became a Gen Z stereotype joke, and "slay" as a reflexive response to literally anything is a recognized bit.
Current usage splits three ways: sincere hype ("slayed the interview!"), ironic deadpan ("got out of bed today. slay."), and meta-commentary about the word itself. It is brand-safe and warm, though leaning on it too hard reads as trying to sound young.
