Back again, I posted earlier.
We actually don't know how the male Sim gets the alien baby, it could be face-hugger thing, a kiss, or anything. In Sims 2, Knowledge Sims usually wanted to see Aliens, Vampires, be struck by lightning, etc. I feel that if you are purposefully having your Sims follow a Science career, you are technically putting them on the path of being abducted by Aliens.
As for the consent thing, I don't think what possibly happens to the male Sim, would not fly in the real world. I don't condone that in real life for males or females.
HOWEVER, this is a game, a fantasy game at that. I feel that we need to divide real life and fantasy. If you spend your time killing Sims for fun, that doesn't make you a horrible person in real life.
At the end of the day, Sims aren't real people, so if you want to play realistic, not realistic, or in between it is up to you.
If I can continue to play with fantasy Sims like Aliens, I wouldn't mind toggles, because so many of them have been nerfed, and I bought the games specifically for that feature. However, I also know that people want Island Adventure for the world, Get to Work for the careers, Vampires for the Goth look, and other stuff.
Sims 4 gave us the option to create Aliens or get abducted by Aliens, which is an improvement, so if you are not cool with the male Sims getting abducted, then you can create them instead.
