In 2014, I did some work on a book for Insight Editions about Ghostbusters, and I was in charge of interviewing many of the people involved with the making of 1984's biggest hit and the 1989 sequel, as well as the cartoon spin-offs. I had a lot of interesting conversations about the film and did things like spend the day with Ray Parker Jr. at his house in his Ghostbusters room.
What was clear when doing the interviews was that there are many versions of Ghostbusters history, and the participants in the first two films all had their own stories, and they all took credit for the same things. It was both revealing and very confusing. It's revealing because it says a lot about the person recounting their version. In some cases, people credited others with a particular moment of inspiration, but mostly, people told versions in which they were the heroes of every moment.