At the risk of seeming unbearably smug, at the end of the day my 'opinion' happens to be the correct one here, and since the most energetic members of the left happen to share your opinion we'll probably get to see this confirmed in excruciating detail over the coming years.
I'm very excited by the idea that you have a method to demonstrate that the cause of growing racism is the backlash against racism rather than the racism itself. I understand that it would just be too dull for words to actually lay out that methodology, but I for one am reassured that it exists.
2. A significant reason for that low turnout was that would-be voters stayed home because they didn't like a PC witch-hunt
That's only a small piece of the picture. The issue wasn't so much boycotting the PC witch-hunt, it was the PC witch-hunt failing to resonate with or energize people who needed energizing.
As I said earlier, I would be super-excited to see any actual evidence that demonstrates your contentions here. Whether on point 2, or indeed points 1 or 3.
And I'm just in awe of the logic here:
1. Most PewDiePie fans are young
2. Most young people are "leftist" (bleurch, ridiculous term. Wtf was wrong with left-wing?)
3. Therefore most PewDiePie fans are leftist.
The ineluctability of it! I *will* grant you that it is likely that at least some of PewDiePie's fans are sufficiently dumb to think that they're left-wing despite holding bigoted views, and will be so outraged to have seen their idol suffer indignities for his videos showcasing bigotry because *irony* or whatevs, that they will skip straight into open identification as alt-right assholes.
Finally: I'm pretty sure that insensitivity never went away as a thing. My female friends tell me about quite extraordinary amounts of insensitivity they experience on a regular basis, right alongside the explicit bigotry. Funnily enough, my white male friends don't tell me about anything similar.