I dont think its a straightforward attempt to come out of it as a hero, since at times he was willing to include himself on the list of people who were not fit to be in charge of the pandemic response.
A fair chunk of pandemic failure that he described wa entirely compatible with his longstanding attitude towards the existing structures of government, and his agenda about how things should be done. Todays performance was a giddy mix of that and more personal stuff to do with specific people he thinks are shit at their jobs, and/or that he has fallen out with at various stages. Not very subtle, especially when contrasted with what he said about those he is full of praise for, or at least doesnt see fit to include in the blame game.
I will obviously never see him as a hero, but if he actually wants to achieve some near-term good with his revelations, in terms of preventing pandemic death, his criticisms need to be carried forwards by all sorts of other people and commentators and applied to Johnsons decision making in the coming period as the government responds to the Indian variant and whaever size wave the variant and the relaxation of measures creates.
My brain is falling out right now beause I decided to reread the many pages of the UK pandemic thread that covered the period of early March through to 24th March. Very many people on this forum had a very good idea of what was going on all the way through that crucial period, but I wore myself out reading it and wont go through it all again now. But along the way there were no shortage of media articles that demonstrated that the government were briefing heavily on the herd immunity approach, especially just before that plan died. And the lag between when Cummings said the u-turn happened, and us figuring it out and/or the media reporting it was quite short at the time, often only hours or a few days.