I love the alien abductions and I would be really sad to see them go honestly! This is one of my favorite parts of the game because I love the randomness of it. Sadly, alien abductions don't happen that often anymore, and that also makes me sad. I love it when my male Sims have alien babies! For me, the aliens have at least a little more to them than normal human Sims, so if I do play with children it is usually Alien children. I don't like it when games control what a player can and can't do because of what a select number of people want. It limits the freedom of a game, especially of games that are rated Teen or Mature and therefore should be able to have darker content within them.
I do think that this could be fixed with toggles, but those would need to be balanced so that the addition of them doesn't nerf the game in any way.
