Yes, that is true, but propaganda excludes truth, most often, whether it's positive or negative.
In this case, the propaganda is that they're not really evil, they're interested in establishing Britain again. The subtext is that they plan to do this by getting rid of all the immigrants and Jews and blacks and whatnot. Same goes for the KKK, their site likes to say they're just interested in making everything equal for everyone, including whites, but anyone who sits in on a meeting will hear nothing but blatant racism.