Yes. I think the key here is that it probably makes us happier to see two choices and choose the kinder, rather than simply living in a kindness-enforced society. At least for me, I derive a lot of happiness simply from my sense of agency, and choosing to be an agent of good will is powerful.
One confounding variable here might be the fact that conservatives are actually less likely to use Google. There has been a strong backlash that I've seen personally, where conservative members of my family actively encourage me to stop using Google because it's in some way "liberally biased" and that it has a "hidden political agenda" and is trying to "impose its radical views on the world." I'm not making this up, there are even books on this very subject. One example is "Search and Destroy."
Google has an advantage in mindshare in that it's effectively the "default" search engine on the web, but its population is still, to a degree, self-selecting. Whether this effect is pronounced enough to skew the data, I can't say.
I guess that implicit in the article is the assumption that this self-selection effect hasn't changed much in the last 4-8 years. The author is careful to stick with like-to-like comparisons.
If on the other hand there is a trend away from Google among certain groups then that would seem to be a problem for Google's branding team! Perhaps there is a market here for a left-wary search engine, say DDG hooked up to conservapedia instead of wikipedia at the backend?
Tom Ptacek certainly made a good case that Google's politics (more precisely, the politics of a few individuals on the relevant team) are informing their search results on occasion:
