HMRC started telling people about this in 2016 I think, anyone who has left it until now to worry about it only has themselves to blame in that scenario.
They've been offering settlements, payment plans etc.
Exactly, all these people who apparently knew nothing about it were just ignoring it and hoping it would disappear or they could get around it somehow. My dad worked at the IR for a long time and they are always willing to discuss repayment and getting as much back as they can reasonably expect. They would rather get back 20% instead of 0% because the person has gone bankrupt.