The problem here is language, not politics. There are some parallels with the John Birch Society back in the 50s and 60s fussing that America was not a “democracy” because “democracy” did not mean the same thing as “republic.” You could argue that they were technically right, but it didn’t matter; people will use the word “democracy” the way they want to use it.
It is somewhat the same with “socialism.” Technically it may be a synonym for “communism,” but that is no longer the way the word is uniformly used, especially in Europe. The classical meaning is generally intended by conservative, anti-communist people and by hard-core, old-time socialists. The more modern meaning is generally used by younger people who really don’t even know the precise definition of communism. It’s the opponents of communism who are usually the ones who can recite the 10 Planks of the Communist Manifesto from memory.
That web site you referenced does seem to be an old-time socialist web site. Some of the planks are definitely in line with modern communism. For example:
The Socialist Party stands for the abolition of every form of domination and exploitation. Yeah, that’s classic communist campaign language.
Social ownership and democratic control of productive resources. Again, that is Plank #1 of the Communist Manifesto, which calls for the abolition of private ownership of property. No important Democrat is pushing for that. Not even Bernie Sanders (see below).
The Socialist Party stands for. . .focusing on production for need not profit. The abolition of the profit motive is definitely a Marxist goal. Again, no important Democrat is pushing that.
So, this site by The Socialist Party USA is pushing classical socialism/communism. But this is not what Democrats believe and practice. Let’s look at just two informative quotes:
Bill Gates: ““Socialism used to mean that the state controlled the means of production, and a lot of people who are promoting socialism aren’t using that classic definition. . .Most people really aren’t arguing against capitalism. There may be a few, but most people are just saying that the taxes should change.”
The World Socialist web site: “As a comparison of Sanders’ positions to these core conceptions of socialism makes clear, his “socialism” is a ruse to prevent the emergence of the real thing.”
The bottom line is that when the term “socialist” is used in campaign literature, it is used to scare, not inform. It is the mirror image of using “Nazi,” which is equally untrue.