I always thought that My Sharona by The Knack killed Disco.
Song was OK but cannot believe it was #1 for the year. Had it on my contest last year because of that. Disjointed and spastic without much tunefulness.
Pretty sad if that is what killed disco.
OTOH I think the perfect linkage between the ‘70s and ‘80s was “Funkytown”. Perfect year, and so much like disco but with the stronger syncopation and electronics of the pop/punk ‘80s.