In that, because of the outrage over Beria's rather dubious sexual crimes, people ignore his real crimes during Stalin's terror and victims of this. It's as if someone were spreading that Hitler was the creator of financial pyramids and people were constantly talking only about this, ignoring World War II and the Holocaust. As if that wasn't enough to convince us that he really was a bad person. And to answer your question, about "the real criminal, if it's not him", no one has heard of these alleged rapes and murders outside of Beria's accusations from the sources mentioned, although Soviet true crime has always been studied in great detail by historians and enthusiasts. This is a typical urban legend, the events of which are known only from itself. I understand your logic "oh, he's a bad person, what difference does it make whether it happened or not?" perfectly. A lot of people believe in any nonsense, just because they think someone is bad and will believe any slander by default (especially if they are so dirty and can be savored for a long time, feigning moral indignation). For example, a lot of people believe in pizzagate or Bill Gates' chipping because they hate politicians and millionaires. But does that mean that it's okay and should be widely discussed instead of their real actions? You can believe me, Beria is widely hated in Russia too as one of the main organizers of the bloody Stalin's terror of the 1930s, even by Stalinists, because it is widely believed that Beria prevented doctors from saving Stalin in order to take advantage of the situation. But because of all this, people in the West seem to ignore all his real (and undeniable) crimes, being fixated on the horror stories about his rapes instead. Which is actually very convenient, because anyone can refute this and create the illusion of Beria's complete purity, taking advantage of people's ignorance of his real crimes. And yes, you can't say "what difference does it make, it's a fictional character" when it's directly based on the scary rumors surrounding a real one. You can't ignore the elephant in the room.
