I am starting to understand that this site is more than what it appeared on first glance. The second I read "secular site," I about left for good. Anyway, I realize this site has specific guidelines here so as to prevent "flame wars" and needless opinionated rants that lead to the equivalent of the lowest-intellect-containing arguments on the internet: YouTube comments. I said all this to say that I want to understand what the term "truth" encompasses. So-called "truth questions" are not allowed because "truth" varies widely among Christians. I get that and that is why I would like any and all (Biblically based) denominational viewpoints to share on the definition of "truth." It is hard for me to define without using the word "true" in some way.
One of the ways Christianity.SE avoids those flame wars is to insist that answers say what whole groups or denominations believe is the truth rather than saying what is the truth on a particular topic.
What is the truth is a matter of opinion, and there are almost as many opinions as there are people. allowing such "truth" questions and answers leads to discussion and debate, and usually flame wars, which isn't what StackExchange is about. SE is a Q&A site, not a discussion and debate site.
What particular groups or denominations believe is the truth is an objectively answerable question. What they believe may or may not actually be the truth, but it is what they believe is the truth. So that becomes a factual matter ("what a church believes") rather than a matter of opinion.
The problem with asking what all denominations believe is that there are far too many denominations to cover in a reasonable space. I happen to think that asking in an open-ended way for the views of various denominations can be useful. But the consensus here is that it's too broad, and leads to a "popularity contest" among denominations, which is seen as not useful. That's why the mods on Christianity.SE frown on such broad questions, even though theoretically they are objectively answerable.