You aren’t understanding the situation. If you are the director of a company who pays himself both salary and dividends, you still have to declare the dividends and pay income tax on them at year end. You pay slightly less tax over the course of a year than a normal employee but only a little bit, as the government closed the loophole years ago. Also, when you are doing that you often lose things like child benefit or even your state pension etc. There’s hardly any difference in tax paid and it’s easy to argue that as a business owner who pays things like rates you pay a lot more tax than a normal employee.
And 19% in Corporation Tax on every single penny of profit you make.