I don't know about this viral load argument. It seems plausible, but I really don't know.
What is f***ing obvious however is that you catch this thing by ingesting virus through your nose and mouth, and you get it into your nose and mouth by either inhaling it, or by getting your hands contaminated and touching your nose or mouth.
If everyone wears a face mask then (a) you don't inhale other peoples' coughed up mucus and (b) surfaces have got less virus on them because infected people are not coughing virus onto their hands and spreading it that way. Also, you don't put you hand in your own mouth when you have your own mask on.
So universal mask-wearing, on it's own, makes a HUGE difference. This has always been the case and it's shameful that we never drove this point home right from the beginning. The best thing the government could do would be to rigorously enforce - with the threat of very severe fines or imprisonment - everyone to wear a mask in public, and especially when indoors.
Anyone choosing to wilfully ignore the rules should be punished severely so as to make an example of them. Noel Gallagher - for whom a £10k fine means nothing - should be given 6 months in prison, for example. This is not a game. Other reckless behaviour which endangers the lives of others can result in custodial sentences, and so should this.