not sure why you put emphasis on "direct evidence". obviously nobody is denying that some people claim to have direct evidence of UFOs. or more precisely, direct evidence of UFOs not only existing (nobody denies that unidentified flying objects exist), but they themselves being evidence of extraterrestrials visiting earth.

i feel like you are significantly misrepresenting the argument made in the blog post and as a result are misinterpreting my critique. again, nobody is denying that some evidence that supports UFOs exists (in the sense of them being aliens). nobody is saying that subjectivity plays no role whatsoever when determining something as fact or not.

the blog concludes with "Seeking truth is great — but mingling truth-seeking with ambitions about consensus is one twitch away from the belief that “forcing my truth upon others is a good thing”". lets look at the context (which the author seems to value so much) in which this statement is uttered: fact checking trump tweets (which the author seems to deem highly problematic) and extraterrestrial aliens visiting earth (which the author seems to say is as reasonable to belief as the opposite). if you do not see the issue here, i don't know what to say.

"alternative facts" are a thing to the same extend that alternative medicine is a thing. if it was reasonable to call them true / if it worked, it would simply be called a fact / medicine.

your time of day and season example really isn't at all what the blog entry is talking about when it discusses facts and "alternative facts". of course your examples are simply overgeneralizations.

in another comment you said that the blog was "just saying one might count those things as "evidence of UFO's" and others might not". it is very obvious that some people DO count those as evidence of UFOs, but that is not all the author is saying. he is asserting that Neil DeGrasse Tyson is "omitting context" when he says that there is "no evidence for the existence of UFOs". obviously nobody is unaware or deviously omitting that people claim to have been anal probed by aliens. NDTs the point is that there is no credible evidence. the author on the other hand is saying that these "alternative facts" are "completely genuine" and "honest disagreement about omitted context". this is nuts.

so what you and the blog entry are saying is that this tweet represents an ""alternative fact,” in a completely genuine and non-insulting sense of the term", based on "honest disagreement about omitted context". because that seems to me the point of that blog entry. he is not just saying that some people believe in facts and others believe in "alternative facts" but he is saying that those two views are both equally valid. which is mental, both in the case of UFOs and trump tweets.

lets take this trump tweet as an example: "The concept of global warming was created by and for the Chinese in order to make US manufacturing non-competitive."

a civil and open-minded discourse concerning such a laughable tweet is simply impossible. it is also not clear to me what the author means when he attests a "universal agreement on the facts". clearly the discourse is not about the "exact words he said" (they are evident, right there in the tweet), but about whether or not these ramblings contain any truth. obviously they do not, which might be hard to understand for someone who believes in the absurd concept of "alternative facts".

"Trump Tweets have shown us that access to, obviousness of, and even universal agreement on the facts often achieves nothing for public discourse. Everyone agrees on the exact words he said, but their interpretation remains individual and tribal." imagine a blog post containing these words getting 41 upvotes on a philosophy subreddit. absolutely laughable.