Do you know what sort of people are being referred to as "Alt-Right" at this point by the left?
Neo Nazis, KKK, Extreme Christian radicals, sovereign citizens, all are called out as "Alt-Right".
Here's the deal, at one time, you COULD call such people "fringe", and indeed, they can still be called that now somewhat. However recent events have shown that these people have been more and more open about who they are or have been exerting more and more influence in the media and even at the political level.
Look no further than the events at Malheur, or the Neo Nazi groups and KKK members like David Duke announcing their open support for Trump, something that they have not really been keen on doing towards Republican candidates in the past (as in just 4 years ago). Look too at how some of these guys are actually trying to run for political office (David Duke is the best example of this, though he isn't the only guy). Also note how Trump and indeed the entire right wing have been slow, hesitant at denouncing such support, sometimes DENYING that such a thing is happening....or even welcoming them implicitly.
And the response from the "mainstream" right is actually quite important to look at as it depicts exactly what their position is with regards to these fellows in terms of overall ideology. In short, there is reluctance to denounce or decry such groups largely because there is a significant OVERLAP of their ideologies disregarding just how far they are willing to go and how blatant they are willing to portray such a thing.
I would really like to see those people who you described as the "real ones who coined the "alt-right" movement". Especially since I have a name for such people too.
Yes it's no secret that the right and left have been deriding each other on their political beliefs. It's not even unusual for that to happen. What's UNUSUAL about the rights beliefs are that, as pointed out, in line with the groups mentioned above which is the reason why they are being made fun of and derided by the left, and also that the belief of the right....don't gel with reality.
The explosion of conspiracy theory (and the popularity of a number of right wing conspiracy theorists like Alex Jones) as "belief" among the right is nothing new, it has actually been considered part of the mainstream right since at least 8 years ago if not more. From the long running birther conspiracy, to the stupid "Bain Conspiracy" pushed by Rush Limbaugh (so stupid indeed that he had to withdraw it afterwards, but the fact he even pushed it in the first place says a lot about him and his audience), even to the extent that they are used on the political level against one of the right, Ted Cruz's dad being acquainted with JFK's killer for instance, leveled by Trump as part of his political plays against his rival. He's still taking cues from Alex Jones and/or conspiracy laden sites like Beritbrats (considering who his current campaign manager is, not surprising!).
This is something that needs no explanation as to WHY it should be mocked, and mocked it is by the left.
So I guess that leaves us with the similarity between the right and the "alt-right".
It's one that's hard to ignore.
That's one way of putting it!
GO FUCK YOURSELF
Not even bothering to hide the fact that they're all Trump, all the time now, are they?
Who is Pepe?