I guess there isn't really a question to answer here but it's more of a discussion thing than anything else.
The idea behind each Stack setting its own policies is that each one can be tailored to a specific community, and that community establishes its own guidelines and procedures. And, as different members come and go, the community adapts and the policies adapt accordingly.
The arguments made on Meta here are very repetitive and common and despite all the discussion, our policies and actions tend to remain pretty consistent. There are two camps -- those who come in and want help on homework problems and think that we should be answering every question that comes in and those who want to outlaw all basic questions or things that are not very high level or specialized in advanced content. The two extremes are very vocal while it tends to be the trend of the majority to take a more even approach.
Both sides have their points but ultimately it is up to the community to decide what kind of community they want. The tendency to ban homework questions is grounded in trying to keep the community that is here happy. Many (not all, but many) of the people who drop in to ask homework questions are only looking for a quick answer and have no desire to participate in the community. They ask their very specific question, get an answer, never accept answers or vote and then disappear until they need another homework question answered. These people have no intention of being part of the community and so we don't look highly upon their questions, and we actively do what we can to suppress them.
The argument made by those who only want high level, advanced questions is that homework questions "drown" out the "good" questions and they have to sort through the 500th question on why F = ma and they miss the questions they are interested in. Personally, I don't buy into this since there's ways to sort and search by tags etc.. But there is some validity to how they feel.
On the other hand, only taking very specialized questions limits to people who are interested in, or capable of, participating. And small communities like that don't function well within the Stack Exchange universe. But the people who want this say "Who cares what SE wants, we want our community!" The solution, whether they like it or not, is to go make their own community because this place just won't work that way. And they have made efforts to go do that.
So coming back to your main point. If you read the posts on Meta and the arguments, it's easy to think we're all a bunch of jerks who are mean and blast people into oblivion. But (now anyway, there is a lot of drama surrounding the topic of politeness on our site), we are actually relatively friendly. Yes, we will downvote homework questions and vote to close them (I did both on your most recent question). But we will not tolerate attacks on people, nor will we post comments on homework questions insulting people etc.. That is not okay.
Our hostility is not very hostile, but when it is, it's confined to Meta (usually) and it's directed between experienced people here (typically). And mostly it's because we know each other. On the main site, when people post things that break policies, the majority of the experienced users are very civil. The anger and hostility usually starts with people who are not part of the community who get upset about the downvote, or upset about a question being put on hold, etc.. And they get upset and start lashing out because the site doesn't work the way they want it.
I said it in chat before and I'll say it again now -- for some reason, on the internet in general, but specifically on the Stacks -- there is a mentality where people show up to play in our sandbox and then get really angry with how we play in our sandbox and tell us we should do it their way. But the thing is, SE as a whole and each Stack specifically, isn't designed to cater to every person on the internet. It's designed to generate high quality questions with high quality answers from experts.
And our experience is that the vast majority of homework-like questions are not high quality. And the vast majority of people asking those questions do not become high quality members of the community. There are ways to phrase homework-like questions so they are on topic, and high quality, and useful to others. And that's what we're looking for. And we will help those who want to get to that point.
So your question on non-linear springs for example, if you could explain the steps you took and why you think those are the right steps from a physics standpoint, we would keep it open. We would be able to say "Well, you assumed X is physically correct but the physics say Y" which would lead you to your answer. But just putting an equation and saying "I don't know where to start" doesn't help you, it doesn't help (or interest) our members, and the answer won't help anybody other than you. Whereas, breaking down to the physics of your question and why you think a spring force should work a certain way, will help others who may be confused about their spring problem.