Yeah, I used to be a "free speech absolutist" too. Used to harp on about how important it is that we allow all views to be spread, regardless of how disgusting it might be... Then I grew up and realized how harmful that idea is to society.
Slippery slope fallacy isn't enough to convince me that having laws similar to Germany is going to lead to oppression or something. These ideologies have no place in modern society, and they should be given no quarter.
These people use your ideal of free speech absolutism against you, and until we realize there needs to be limits, we will never progress as a society because all of our time, focus, and resources will need to be on fighting this shit over and over and over.