Having seen what happened in Southport when people thought they knew that the man who murdered the children was an immigrant, fuelled by people with a racist agenda, I'm not surprised if there was reluctance to point out the race of the abusers.
As has been said, not all data collection included race, so again, it's not surprising that dots may not have been joined.
A willingness to assume motives to others is rarely helpful, but as people are often ready and willing to do so, ('he was scared of X', 'they didn't want to offend Y', they didn't want to be labelled Z') it's also unsurprising that we are where we are.
I hope this enquiry can reach a conclusion, but suspect that a paucity of evidence, and too much speculation and scaremongering will get in the way. As we can see from this thread, it has started already, and things are not under way yet.