I've heard for a "rule" that you should not capitalize the words in the title of an article, when the title is in the form of a sentence. For example:
Pneumonia is contagious. (As opposed to Pneumonia Is Contagious.)
I'm aware that this is purely a matter of style and there are different recommended styles, but my question is: Is this non-capitalization even "a thing?"
EDIT: I've found this on Capitalize My Title website:
The other major type of title capitalization standard is sentence case. Sentence case simply means you capitalize the first letter of a sentence and nothing else as opposed to capitalizing almost every first letter in title case. It is the same across all of the four styles.