"we will soon be updating our Terms of Service where your earnings from YouTube will be considered royalties from a U.S. tax perspective (we’ve already made this change to the Terms of Service for U.S. creators in November). This may impact the way your earnings are taxed, and as required by U.S. law, Google will withhold taxes."

So you will have to file a tax return and get the money back just like every other income earner in the country. The real issue imho is that the bulk of youtubers probably aren't properly filing any returns in any country.

I have a young guy working for me who does game streaming on weekends. I think he earned a few thousand dollars last year. He had no idea that such income was taxable, that he would actually have to hand over part of it to the government despite it not coming from his fulltime job. I think he would prefer google withhold those dollars.