The current policy on "designer-reasons" questions states that they are off-topic and are considered to be off-topic because they often receive answers that make guesses and do not involve actual citation and quality evidence. This is also explained quite well in KRyan's answer to the question "Are these “history-of-gaming” questions designer-reasons?"
Clearly "designer-reasons" questions and "history-of-gaming" questions are similar, if not directly related.
Meanwhile, "history-of-gaming" questions are on-topic and, under a number of questions asking about designer-intent, I have seen comments along the lines of, "if we convert this into a history-of-gaming question it will work for this site".
Clearly "designer-reasons" questions and "history-of-gaming" questions are different.
The following are some history-of-gaming questions that are currently closed (often only after the policy change I linked at the start, and many with lots of close and reopen votes across their life so far):
- Where does the stereotype that wizards can't wear armor come from?
- Why did D&D Paladins originally have a requirement to be Lawful Good?
- What explanation do the D&D devs have for designing spontaneous casters to lose out on a spell level compared to prepared casters?
- Why did the designers make it so chromatic dragons can't shapechange?
- Have any of the designers of D&D explained why Strength increases Hit Chance?
- Are there examples of priests/clerics having water creation abilities that predate D&D?
- What ever happened to rolling for stats, encountering class trainers, etc?
Most of these questions have highly-scoring, (though that doesn't mean much since the questions were on-topic) lengthy, and detailed answers with references to various quotes, documents, and facts.
There are also the following three questions which have no positively-scoring answers:
- How has the focus on roleplaying versus combat in D&D changed in the years since its inception?
- How and why has D&D changed its character generation across editions?
- Why do bards and druids get Heat metal?
The problem for me is that the following questions (and others) are currently open:
- Why, from a lore perspective, are druids the only class who can cast the Flame Blade spell?
- Where does the elven "trance" come from?
- Why is Armor Class called that way?
- How has D&D's guidance to DMs on when to extrapolate from written rules and when to improvise changed over time?
- What is the origin of Backgrounds in D&D 5?
- Why are Ghouls not proficient with their bite attack?
- Why are skeletons lawful evil while zombies are neutral evil?
- Why are the beholder deities chaotic evil?
- Why do some classes start with fewer trained skills?
- What Works Inspired Paranoia?
- Why do druids use scimitars?
- Is Morrowind based on a tabletop RPG?
Many of these questions have highly-scoring, lengthy, and detailed answers with references to various quotes, previous editions, documents, facts, and even quotes from the designers.
Is it just that I'm allowed to ask about designer-intent so long as I can shape or contort my question into being about either history or lore to ask effectively the same question but with different wording?
I wasn't here when "designer-intent" questions were made off-topic, but I know that they were made off-topic because of the type of answers they so commonly received. And yet, even those history-of-gaming questions with excellent answers (listed earlier) are currently closed.
I'm honestly confused and the reason I'm asking this is because when I see a questions like "Why is a round 6 seconds?" or "Why are Ghouls not proficient with their bite attack?" I am utterly lost as to whether or not these are on-topic or off-topic and thus completely unsure whether they should be closed or open.
Are questions like "Why is the D&D gorgon a metal bull?" and "Where does the stereotype that wizards can't wear armor come from?" and "Why did D&D Paladins originally have a requirement to be Lawful Good?" and "What inspired the D&D version of the Rakshasa?" about designer intentions or the history of gaming?
How can I tell, and when should I cast my close vote?