Just because Theresa May stands up in the HoC and announces such and such does not make it the truth, and therein lies the problem.
And what is a "dossier"? Is it chapters 1 to 10 fully bound and to be read as a book, or could it be chapters 1 to 10 delivered as weekly instalments, but still intended to be read as a book, or if the chapters are delivered individually do they get relegated from "dossier" to the status of "letters/files"?
There is now a lot of evidences, much of it admittedly circumstantial, that these events took place and that senior figures were involved over a period (allegedly) of 20 to 30 years, so it is not an attack on Maggie's government. There is a worry that the culture(s) at the time, in the police, NHS, Social Services, Westminster..... were to hush-up, minimise or even ignore the allegations of abuse victims.
It is already known that Harman, Dromey and Hewitt were, at best, neutral in their dealings with PIE when they were in positions to bring it down, so Labour is also in the spotlight. And the LibDems, with Jeremy Thorpe and Cyril Smith, are also not in the clear.
If it takes a public inquiry to clarify the circumstances surrounding such serious accusations as are currently being made then what is the problem?
And Suff, if you are a suspicious GOM, then so am I, but from a different POV.