That said, the optics don't look great. In a rational world it wouldn't be a big deal, but this isn't a rational world and there will be people who try to justify their own reckless behaviour with "Will and Kate did it".
It gets worse and worse - now the government are all over the place in terms of their own messaging about the tour.
Having originally been billed as meeting frontline key workers, e.g. NHS staff, care workers etc, culture secretary Oliver Dowden (you know the guy who wanted 'fiction warnings' on The Crown) has said that their visit to Cardiff was about visiting cultural organisations. Important, no doubt, but hardly on the front-line of the fight against covid. And they visited Christmas at the Castle - a Christmas visitor attraction at Cardiff Castle. Yup, top idea encouraging people in a city with 322 cases per 100,000 and rapidly rising to attend a Christmas festival (if it's OK for them Royals, let's get out there and spread that virus)!
And then number 10 seems to have no idea - 'After initially saying the Cambridges' tour was a "matter for the palace", No 10 said Boris Johnson welcomed the "morale boost" it would provide.' Sounds as if this was all organised without any proper involvement of the devolved governments in Wales and Scotland, and increasing looks as if the UK government had no idea either.
And after 'reindeer-gate', we now have 'secret-santa-gate' in which the Cambridge's share secret santa presents (opened there and then - no gloves or masks etc) with complete strangers ... in the part of the UK with the worse case numbers, and rising. Did anyone tell them that the virus can remain viable on packaging for a number of days!
It's almost as if they've been placed in one of those health and safety videos where you have a character who does everything wrong in terms of safety to show others what not to do. Sadly there will be plenty of people who see this and think that its OK to be trotting off to a busy visitor attraction in a city with a high and rising virus problem.