I don’t know about hardcore, but today I’ve been reading the interviews in The Art of Point & Click Adventure Games, where Ron (Rob?1) Gilbert actually mentions that Spielberg was a “huge gamer”, who wrestled the mouse from him during a demo of Indy3.
1 A “Rob Gilbert” is credited for Maniac Mansion on the page preceding Ron’s interview, and it’s by far not the only mistake I noticed on the first 60 pages 
.