Wages are always given gross here so if someone is earning 200k a week would normally be before tax is applied etc.
There are two sets of taxes and fees. There are taxes and fees the employee pays and taxes and fees the employer pays. So yes, you earn say £200k a week (lucky you)- sure, you will then have taxes and fees taken out... but your employer will also be paying taxes and fees separately. It's probably different for super-high earners, but I've always been told by people who run their own businesses that the wage you pay your employee is only half the cost associated with that employee.
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