In some respects, true, but that isn't always the case.
Say you own a company in the UK which sells widgets, but you also own an offshore company that also sells widgets. If you are dealing with a Chinese company, you could use the offshore company to do the deal, paying little to no tax. The money then resides in the offshore company and has never gone through the UK - either as a business or personal. As an individual you could own a credit card that you use to spend in the UK, which goes back to the offshore company. In additional, the offshore company could buy property in the UK and no tax is paid. There are various other tricks and nuances that can be employed to help minimise tax paid - completely legally.
I bet it isn't always the case too, right? I actually wanted to say that the fact of owning a foreign corp doesn't mean anything. It may be used to avoid some taxes, or may not.
I can even give opposite examples, like when someone comes to the US to run a startup in California. For the country of their origin they definitely opened an offshore corp (in the US in this case) and don't pay taxes on it (they still pay to the US gov though). It's just more convenient to have a US corp rather that a corp in their home country, and not because of taxes which may be higher in the US.
Say you own a company in the UK which sells widgets, but you also own an offshore company that also sells widgets. If you are dealing with a Chinese company, you could use the offshore company to do the deal, paying little to no tax. The money then resides in the offshore company and has never gone through the UK - either as a business or personal. As an individual you could own a credit card that you use to spend in the UK, which goes back to the offshore company. In additional, the offshore company could buy property in the UK and no tax is paid. There are various other tricks and nuances that can be employed to help minimise tax paid - completely legally.