This an incoherent and, frankly, silly way of thinking about the issues here. All treaties - all contracts - involve a surrender of freedom of action (“sovereignty”). https://twitter.com/davidghfrost/status/1332291822442467329

The question is whether what you are agreeing not to do is something you value doing so much that you will sacrifice all the benefits of an agreement in order to keep the ability to do it.

So when the EU insists on the UK operating a robust and independent subsidy control regime, the meaningful question is whether the things we couldn’t do in such a regime are things we really want to do.

Do we want UK public authorities (UK government, devolved governments) to be able to throw money at who they like without legal recourse for those adversely affected and without robust checks on effectiveness and value for money?

What things does the government actually want to do that couldn’t fairly easily pass through such a well-designed robust regime? And is the ability to do those things (whatever they are) worth the costs of a (permanent) no deal with the EU?

Remember, this is a government that has already agreed some hard-edged subsidy commitments with Japan. https://uksala.org/subsidy-provisions-in-the-uk-japan-comprehensive-economic-partnership-agreement-what-are-they-and-what-do-they-mean-for-the-uk-eu-negotiations/. It is also a government that promised in March ( @michaelgove to @CommonsFREU) to have in place a “robust” subsidy regime “that will satisfy the EU.”