Well, I think by this we are scaring new users, in fact I really
touched it with my own friends, they are afraid of both asking and
answering although their previous questions/answers were really not
bad, I saw them.
Frankly, you and your friends need to grow thicker skin. N.B. I did not say you or your friends are flipping idiots. But there's an aspect of fields like programming that I don't think people in general fully appreciate, which I think is the crux of the question.
When it comes to programming, and the STEM fields in general, criticism (via downvotes, for example on these sites) is not only to be expected, it is entirely welcome and common practice. It's why the science and engineering fields work. It works because we keep correcting ourselves and our peers. It's how we compensate for the fact that we are human beings and make mistakes. It's called peer review.
The same principle happens on these sites. You know why Stack Overflow is one of the most visited programming sites there? It's because there's little tolerance for crap like the kind you find on other sites, and all the unique Stack Overflow visitors know it.
The fact that Stack Overflow is one of the most visited programming sites means there really is a responsibility to make sure the information is as good as possible, and that the right questions are asked. When people listen to you, it is incumbent upon you to be as accurate as possible. Unfortunately, some celebrities and journalists have not yet realized nor understand this, which is why I can't even watch more than 5 minutes of television in one sitting without feeling like I need to defenestrate something!
You need to realize that none of the criticism that we make is directed to you as a person. They are strictly, and solely targeted to the content of your questions and answers. It's not out of spite, we really want people to have the best answers and the best questions, but sometimes a downvote is the correct and ethical response. Now, if someone came along and commented on your question "this is a stupid-@#$ question you %^&*ing @#$!!" kind of thing then you would have a legitimate complaint. But I haven't seen anything like that.
I'm sure my professors would love to give A+'s to everybody in their classes, but that's not ethical nor honest if they all haven't demonstrated their competence. Unfortunately people are raised to believe that their entire self-worth is dependent on a bunch of numbers that in the long run doesn't really matter. Last time I remembered Stack Overflow Reputation isn't a recognized SI unit that we use for any objective purpose. What matters here is technical accuracy. That's why "high-rep" users are more than willing to give up a bit of their reputation to downvote. And I doubt that "high-rep" users would care about an increase in downvote cost simply because it's still a small percentage of their rep, as you've pointed out yourself.
Yes, I wrote this answer on a soapbox, so let me end on a positive note. If you want to avoid downvotes and close votes, the best way is to forget about them and learn! Study! Do honest research! Because any other way is cheating, and you'll benefit by gaining more knowledge. Must I remind people that knowledge isn't a bad thing? And if anything, use it as an opportunity to show the community that you care about the quality of your questions and your answers! We would love to see good, quality information, since there's enough crappy software and crappy programmers to fill an entire site!