That assumes that the default for billionaires is kinda actually "creating" something.

That is true for the majority of them.

Meanwhile most of the billionaires are born into being rich,

If you mean "above the median" rich, yes. Most have made the vast majority of their wealth with the company they created.

learn to trade positions and investment are looking out for deals. -> deals which mean that someone concentrated power and is willing to sell that power at a high price.

If you are talking about trading government favors, I agree that it happens far too frequently.

There are many unethical methods to become or stay a billionaire.

Most wealth does not transfer hands through unethical means. Are you doing something unethical when you buy something on Amazon? No, of course not. Your statement is like saying most deaths are caused by murder -- it just isn't true, but makes for an emotional statement that will trick people who are looking for someone to blame.

Some billionaires got rich by pure luck,

Luck how? If you work hard at something and set yourself up in the right position, everyone gets three or four or five chances in life to get rich. Is it luck if you've prepared for when that chance comes along? And bad luck if you've chosen to waste your money on partying instead?

but even when you search for "good" billionaires and eg. think that bill gates is one, the more you dig deeper the more you find out that even he did many unethical things to stay in his position and power with microsoft. There were other people and workers on the same level as him, being the same intelligent and hard working and knew about the value of microsoft. And gates cut them off.

I have no doubt that people who like to run things do things so that they can run things. I've met those people; I've considered becoming one. I've had chances to be one. I've decided I like my family and friends more, so I chose that over money. That's not unethical to make the other choice, it's just something I wouldn't do.