Both "Star Wars" and "Alien" were created by 20th Century Fox (which is now called 20th Century Studios and owned by Disney), so this crossover could have taken place with almost zero red tape.
If you want to ruin people's childhoods, you need to do it by abusing them physically/sexually/psychologically when they're children. Or by neglecting them when they're children. Not by making low quality movies and shows.
