This is ignorant as fuck. First of all, there is no more reliable group of voters in the country than progressives. Not even MAGA members have shown up at polls as reliably for Republicans as the left has for Democrats. Still, the Democratic establishment whines about leftists staying home to excuse their pathetic losses, and morons eat it up.
Also, even if there were any kind of truth to this narrative, trying to win an election by shaming voters is dumb as fuck. No voter who is as fickle as you think the left is, is going to decide to show up because you shouted insults at them. This isn't a strategy to win elections, it's a strategy to excuse losing them.
It's not "left" voters saying they will stay home, not in significant numbers. It's Muslim voters or, more precisely, it's voters who know the names of the people being systematically slaughtered with US weapons. While I agree that voting Democrat is the best bad option for Palestinians, I can't get behind shaming someone for not voting to elect someone unrepentantly responsible for blowing up their loved ones. If they can't stomach voting for Harris, I don't blame them.
Read your comment that I responded to. There is no indication whatsoever that you aren't among the large contingency that actually thinks these freaks are leftists. When you mimic idiotic Democratic establishment talking points, you will get treated like a Democratic establishment idiot.
Way to fail to make the point.