I disagree, and despite Boris saying that, I don't believe any independent fact checker have suggested it was the most generous or sweeping.
It's also been made clear (and even he has briefed this in order to up his 'tough choices' persona), that he would have gone for something less generous, that covered less people, and that ended sooner.
All the talk of "grown-ups" is worrying, because there's a strong argument that the last supposed grown-up, George Osborne (who took over when the country had already come out of recession), used the 2008 crash as an excuse to decimate public services. The talk now is all about pain, but clearly it's not pain for Conservative ministers and their friends.