Increase the tax-exempt allowance to up to €50,000 per year; tax any amount above that at the personal tax rate; and then include precious metals and cryptocurrency as well.
@GreenWash 50k will surely remain a dream, but in principle I agree with you. The flat-rate withholding tax has to go—it can't be right that people who make millions on the stock market pay less in taxes than those who work hard for their money.
That's exactly the point. Income from employment is sometimes taxed at a significantly higher rate than investment income. If we want to make the tax system fairer, we need to look at the system as a whole—not just individual types of income.