The "irony" in supporting that party I believe is a stretch. I don't see how support for some neo-nationalists is inherently "anti-freedom"; would that not apply to any party arguing against open borders?
My personal belief is that professional discrimination because of political support is a very slippery slope, and I honestly think that a lot of people directly or indirectly advocating for it are not fully understanding of what this means and where that slope ends:
When asking about professional boycott for "questionable" past positions (like being gay in Turings time) I only get silence in response because people presumably realize that such witch-hunting often ends up looking really bad in retrospect.
edit: I just misunderstood your last point, completely agree.