Propaganda is what it is, what it is not is forcing anyone to believe anything. Propaganda is not evidence based, and to avoid being fooled by propaganda, a person needs to investigate the claims, look at the supporting evidence, or lack of, look at the agenda behind the propaganda, and make an informed decision for themselves.
You as an individual decide whether you want to believe what someone is telling you.
"Just because you don't know or perceive any scientists that are trying to do so, does not mean they do not exist. I have met many in my life, and they are currently working to impose their dogma just like the religions of old have done."
This is true, I certainly don't know every scientist in the world, so it is possible that there are scientists like this that exist. How do you believe they are trying to impose their dogma? Do you have any examples of this. How do psychologists impose their views on others?
Hitler was a political figure, not a scientist, and their was no scientific basis for eugenics, or the beliefs of Hitler himself. It was the people who followed this man's ideals and views, that murdered. These people followed either because they believed his propaganda, or because they feared punishment if they didn't obey.
"People can expect whatever they want, but that does not make it so."
If you make claims that you can't back up with credible evidence, you will simply not be taken seriously, and your claim will be dismissed. It is not up to the person you are making the claim to, to prove you wrong, it is up to the person making the claim to prove the claim. The person making the claim can either prove it or not, nobody is saying that they have to, but the burden of proof is on the person making the claim.