I have finally found the perfect question to kick-start this discussion concerning what I believe is a growing undesirable behavior on Worldbuilding
The OP wasn't just a new user, before I upvoted her question she had a single reputation point and hadn't taken the tour yet. She was as new as new could be! And the very first reaction she received, both in comments and in answers, is "that's impractical!"
There was a day when participating worldbuilders would pick up the gauntlet and throw impracticality out the window to come up with creative, imaginative, clever, weird, funny, stupid, even controversial ways to solve the OP's problem. But today, we're growing into a habit of stating, proverbially... "well, you can't do that in real life, so you're screwed."
Real life cannot be an overriding limitation to worldbuilding
I have not taken the time to sort through the questions. There's a lot of them! It's actually exciting to see so many new users and new questions! But there have been enough questions to throw the proverbial flag in my consciousness. I've even started catching myself doing it! (And I've been chastised by others for not doing it!) Far too frequently either...
Questions are appearing with startling frequency asking if it's possible for something fantastic to happen in Real Life. Think of it as, "please show me some blueprints to build my Death Ray!" That used to be rare. At least it feels to me that it used to be rare. And I suspect it's a consequence of the community's shift to expecting all questions to be answered from the perspective of Real Life. At least, if you read through our answers of the last few weeks... it sure looks that way. We're apparently becoming the place, not to figuratively bring imagination to life, but to literally being imagination to life. (If we could do that, even rarely, we should create our own site someplace where every post isn't Public Domain so that we could file all the patents!)
The problem is that imposing Real Life on any question without the express invitation by the OP to do so seriously limits the value of the site. To be blunt: there's no reason for the site to exist if questions can only be or should only be answered from the perspective of Real Life.
I'll create an example using one of the question types I hate the most: How could my fantastic creature evolve? I hate those questions because, simply, the creature didn't evolve in Real Life, so obviously there weren't any examples of evolutionary pressures in Earth's history that could justify the creature. Shame on me! I still hate the question because, frankly, what's the use of that information in any story, really? But who am I to forbid a creative and, therefore, productive answer just because I can't see beyond the limits of Real Life?
Rather than welcome a new user and ask questions clarifying the user's intent for the purpose of creating imaginative solutions, we immediately started complaining and pointing out the unreality of the question. On Worldbuilding! Frankly, most of the linked question's initial comments were little more than calling the OP's question "dumb" and, funny as they might have been to read, were actually quite mean and restrictive.
Proposal: Science is a great TOOL for helping worldbuilders build their worlds, but it is NOT a fundamental limitation save in the case of the hard-science tag
Even the science-based tag shouldn't (and doesn't!) mandate that science is the only expression of the solution. It only means that science should be the stepping stone we use to justify or rationalize an imaginative solution. But it seems to me we are, less and less, believing that. Instead, the site appears to be imposing science as the one and only valid perspective.
If you, the reader's, knee-jerk reaction to any question is, "you just can't do that!" you should train yourself to recognize that moment and force yourself to realize that you're not being creative.
I'm going to leave you with a personal, and therefore very blunt, consideration:
If hard science is the world you want to live in, you're participating on the wrong Stack. While we allow querents to tag their questions with the hard-science tag because, sometimes, the querent wants to express an idea as closely to the rules of real life science as possible, that simply is not the go-to first solution for worldbuilding. Participants who believe any (if not all) questions should be addressed principally by Real Life are welcome to leave this Stack and participate on the Physics, Earth Sciences, Astronomy, Geology, and Space stacks. Worldbuilding is a place where scientists and artists combine their experience to bring flights of fancy to life and imaginatively realize the most beautiful expression of "what if?"
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