The idea of an "inquiry" for this is so utterly hilarious. What is he expecting it to find? That leaving the EU was a disastrously unpopular decision and that anyone can wave a flag?

Also, they view Rule, Britannia as a modern, relevant, unironic thing? I see that as the British equivalent to when Americans are like "MURICA, fuck yeah, guns and lifted trucks and bald eagles and worshipping the founding fathers!" Which is to say, incredibly cringy.