The thing is, do you have only 5-10 FB Friends with eerily similar sterile accounts in a little-self contained social graph? Have you added a college to your profile, but have no Friends from that college?
I've got a fake FB account for the same reason you describe, and I don't bother go to the efffort of puttiing in the sorts of fake details that these accounts have.
I mentioned that this happened on Conservative sites, and it was during the Primaries. It seems unlikely that, under those circumstances, people would be so shy about expressing their preferences.
Also these are not just stand-alone fake accounts with no friends created for making comments....these are curated to have enough details that make them look plausible to an unsophisticated automated detector (or overworked FB abuse department employee), but they have few friends, all with similar sorts of profiles, and no signs of activity except for posting comments.
I do agree that there was an element of "shyness" and self-censorship, but I expect it was from supporters of other candidates, who would not want their Real Names and identities to get embroiled in fights with fake profiles.
There's an angle that hasn't been explored that ought to be: a lot of news and political commentary websites used to run their own comment systems for articles or use pseudonymous services like Disqus, but these were overrun by "trolls" and spammers.
Many then switched to Facebook, presumably hoping that the "Real Name" policy would improve things.
The interesting thing is that clicking on many of the Facebook profiles on these comments leads to curiously sterile profiles, with a few friends. Some of the most vehemently pro-Trump comments seem to have originated from these accounts, especially on certain Conservative sites during the Republican Primary season.
Facebook seems to have no interest (or ability) to clean this up.
Another useful tactic is to archive news and commentary (left and right) about current political events, both for accountability and perhaps, to prevent the rewriting of history in the era of "alternative facts".
*I hope you got the name. I've redacted it for obvious reasons.