@newnortherner111
I was chatting about this with a friend yesterday who's a civil servant with access to a lot of information. He told me that Shapps and Raab were totally sidelined on this and were furious, whereas they are usually at least consulted in some token way...
The decision is clearly political: you can fly from Réunion to the UK via a range of places, notably but not only Mauritius (though that may now be impossible given the new restrictions in Réunion), so the beta variant excuse is obviously crap.
If they do put France on the red list in the coming days or weeks, there will be fury in the UK, as people have now (re)planned trips based on the amber plus rules invented solely for French travel. If they did that, there might be a huge U-turn a week later when BJ twigged he'd pissed off a lot of his voter base with holiday homes in France...