VAT is trivial for businesses to deal with. You add x% onto every invoice you issue. The VAT due to be paid to the government is a simple sum of the amounts distinctly shown on each invoice you issue minus the sum of the VAT amounts on invoices you’ve paid. Income/employment taxes, corporate tax, import taxes, etc are orders of magnitudes more complex, dynamic and subject to legal interpretation. I was a small business owner for a while years ago and did the VAT myself. But there was no way I would even attempt employment or corporation taxes - covered by endless legislation and changing every year - that was a job for the accountant.