Celebgran there are many old men in prison for offences of historical abuse, going back years. Some die in prison. The ones who have abused within the family have got away with it till the next generation starts arriving and the victims realise their own children are at risk. With support from partners, they often feel more confident about telling the authorities. It depends on the details of the abuse, whether a conviction can be obtained. Of course, adults tend to make more articulate witnesses.
Old men in paedophile rings have been prosecuted many years later, if they are still alive. Offenders often decide to name names when they are in prison.
Re: the high profile Thatcher era politican. His name and others have been bandied about with no result for years. Lots of info on the internet if you google 'politician named in North Wales abuse.' His name trended on Twitter at the weekend, so it's no secret. Interesting that so many politicians have been shifted overseas or encouraged to resign because they abused children. Such corruption. I wonder when public schools are going to have the spotlight on them?