That article is just rubbish.
I watched the PM on live tv. The context in which he said 'take it on the chin' was ignored. The article says that it was ignored, there was a reaction on here and elsewhere about his comment.
This is from the Mirror who quoted him at the time over a month ago:
"At the moment what they are telling me is, actually, slightly counter-intuitively, things like closing schools and stopping big gatherings don't work as well perhaps as people think in stopping the spread," he said.
"One of the theories is perhaps you could take it in on the chin, take it all in one go and allow the disease to move through the population without really taking as many draconian measures. I think we need to strike a balance.
"I think it would be better if we take all the measures that we can now just to stop the peak of the disease being as difficult for the NHS as it might. I think there are things we may be able to do."
As you can see, 'one of the theories' 'I think we need to strike a balance' 'It would be better if we took all the measures we can now to stop the peak being difficult for the NHS'.
However much you wish he had advocated 'taking it on the chin' he did not at any point suggest that. Boris has not always covered himself in glory, there is plenty of material out there to attack him with if you are so inclined, but this instance is not one of those indiscretions.
I'd not engage if I was you. I'm no fan of Johnson but haters will always be haters - and there appears to be a few on here. There are also some sudden experts on the situation who would have got everything right - despite no government in the world having done so.