If anybody can legitimately avoid paying tax, then they should. In fact, they have a moral duty to - they are better at spending their money than any Government. All Governments and public bodies are wasteful, because it’s easy to spend other peoples money.
Show me somebody who would rather pay £100 tax when they need only legitimately pay £50 and I’ll show you a liar.
As far as we know Sunak’s wife has legitimately avoided tax. She’s paid the amount she’s required to pay in the Uk, and the amount she’s required to pay elsewhere. She’s done nothing wrong.
So YMB is correct - it comes down to jealousy. Legitimately avoiding £50 is OK, but
Legitimately avoiding £50m is not OK.
Also, anybody who has an ISA is legitimately avoiding tax.
I see no difference.