I advocate for everyone to use basic declarative statements when they are not completely certain, with uncertainty left implied and up to the reader to figure out.

If the writer is certain about something or wants to make an absolute statement, then that's when the verbosity comes into play. That's when the writer can start to add all the fluff words.

That's a convention that's way better, because the large majority of statements and propositions aren't known with certainty. I am exhausted at having to read long winded prose with endless "maybe" "mostly" and so on, with the obligatory "we don't know this for sure" at the end. I don't come away thinking you're humble, I am just annoyed that you've wasted my time when it was blatantly obvious you were saying something not absolute.