He said he didn’t understand the issue and talking to abuse survivors helped him understand it better, and that led to him changing his view. To me, that sounds like a person simply updating their views in response to new evidence-new to them even if much older to many others. Labelling it as “back-pedalling” seems to me to be needlessly uncharitable to him
It might be hard to understand why it took him so long to realise this-but I think you have to understand he occupies a very different position in society from most people, with the result he is often ignorant of mainstream trends, or feels no motivation to care about them. His former position on this was actually reasonably mainstream on the Left in the 60s/70s, so in itself far from unusual for someone of his vintage, what was unusual was it took him so long to abandon it (or at least learn to shut up about it). But, if you try to understand him, rational explanations for it taking him that long may occur to you
I’ve never seen any evidence he has any actual sexual interest in children - just that children are somewhat of an intellectual abstraction to him. Before I became a father, children were somewhat of an intellectual abstraction to me too. I think that is a large part of why the wrongness of his former view was not obvious to him in the way it is to many others