Re: "This measure is expected to impact 170,000 individuals" . . .
in other countries you are a citizen, in the UK you are a "subject".
Not true. The status of "British subject", which applied only to overseas non-residents anyway, was abolished 30+ years ago. Look on a British passport, it clearly states "British citizen".
My experiences of dealing with the UK tax authorities have been generally positive, and a far cry from the unhelpful incompetence of the French ones, for example.