Bit of a strange question to be honest.
"are victims bullshitters?"
The way that question is phrased already assumes sequence of events, like asking "do raped women lie?" Or "do abused men always tell the truth?"
First, no matter how much of a victim someone is, it is still possible for them to lie as long as they can speak and some subsect of victims will lie.
Second, the lie may be part of what the claimed victimisation is about. It's like the "raped women don't lie" meme. Even if that were true, you still have to identify the non-raped women from the raped women, as there is no reason why someone couldn't claim to be raped when they're not.
Third besides the victim status itself, it is also possible for victims to exaggerate the degree of victimisation.
So to get back to your question. Are victims bullshitters? No. Of they're victims, then they're not bullshitting about being victims, because the qualification itself is that they're victims.
Do some that claim to be victims lie? Of course. This particular lie led to the "it was not true. But in my mind, it was real".
View attachment 1238741
Ha-Ha-Holocaust - Herman Rosenblat: "It was real in my mind" (Feb 2009)
www.bitchute.com
Note that it doesn't say anything about the veracity of the holocaust. Only something we all know. That people can lie.
As for your other questions.
Is it illegal to question the number of russian deaths in my country? In Russia itself?
Do people who investigate details about it in russia that result in conclusions that deviate from mainstream get harassed, imprisoned etcetera? Were the millions of russians casualties of war or intentionally murdered? That's the central difference between the two things you're comparing.
As to what can be gained, I've already discussed that. Lots if money, political immunity. But there are many more motivations. The guy above did it for fame. I think spite and vengeance can be another motive. I'm not saying that everything was a lie. I'm saying there is more than ample motive.
If you consider the theory that the holocaust was smaller than it is in the official version and if you consider that it wasn't a complete death machine. Assume that for a second, the way you asked me to assume whether victims could be liars. Would it really be hard to understand that someone like Otto Frank, anne franks father, would have motive to embellish events to exact greater vengeance on the people who brought the conditions that caused his daughter to die hundreds of miles from her home?
I think in essence you were asking about motives, so I return the question about motives.