Indeed. But many pollsters (like Nate) acknowledged this huge miscalculation in hindsight, and have tried to dissect that and predict with that in mind.

In fact, the original source addresses this and discusses the topic extensively. It’s most of the interview:

I think Democrats have the emotional feeling that when there’s a polling error, it is against them. Because Hillary Clinton and Joe Biden and just in general — polls actually have repeatedly underestimated Donald Trump. But is that true? And is it particularly true in midterms? Have polling errors been consistently against Democrats?