It leaves so many unanswered questions, e.g. what happened to Short Round, and why Indy doesn't believe in magic in Raiders.
And the reason was ridiculous. George Lucas said it was because he didn't want to make the Nazis the villains again. It's his screenplay, the villains can be whoever he wants, regardless of chronology.
And the movie is set in China and India, the Nazis never went near there.
1) Short Round is just a kid, he has to go back to school or whatever. Indy has his own life as a university professor. This is like asking what happened to Willie Scott - same reason, it didn't work out between them. Not practical.
2) Actually, Indy was knocked out for a quarter of this film. He drank the blood of Kali and then he wasn't Indy anymore. That's akin to being drunk on alcohol. Thus, Indy probably couldn't remember that much of this adventure if you think about it. Nor did his psyche want to remember any of it.
The supernatural magic of this movie was also not anything like the Ark of the Covenant's supernatural power.