BBc article here.
It quotes senior tax and accountancy figures saying that HMRC expects couples to share information, and also will be ready to pass certain information about one partner to another to let them ascertain if the other pays HRT. This undermines independent taxation of couples (in place since 1991) and runs counter to the principle of taxpayer confidentiality (a formal part of the tax system since 1803).
Revealing someone's tax records is currently a criminal offence for HMRC officials.
That such senior figures have concerns, calling it a bad tax, is concerning. And changes to such long-standing principles of the taxation should surely have been subject to more attention.