Right but if everyone has to declare the wages, It becomes a competition right, so it might be clear that a company pays minimum wage and b company pays minimum

Right but if everyone has to declare the wages, It becomes a competition right, so it might be clear that a company pays minimum wage and b company pays minimum wage +25% in fact I think it would be the opposite problem that to attract talent you might say this job pays up to $1 million a year (theoretically)