Dimples I was told on the here yesterday that I was imagining people with disabilities getting abuse (e.g. my son who is learning disabled was told to fuck off by a man in a jag). I think your story is all too common.
And meanwhile elsewhere on mumsnet we’re being told that only people who can be guaranteed to behave appropriately should be allowed out. That’s my learning disabled son out then. That attitude (which is rife in another current thread) is every bit as much disablism as this horrendous act. If you think that people with learning disabilities shouldn’t have the same right as access because they ‘might’ scald a baby (they might, so might anyone - I was scalded as a small child by someone with no learning disabilities in an accident in public), or they might push someone in the road and make them die (they might, so might anyone I was knocked into the road by a middle aged male commuter rushing past me last week, I suppose that could have made me die of a bus happened to becoming past), then you are every bit as disablist as these yobs.
I think my son would probably rather be pelted in flour than told he’s not allowed out near normal people - which isn’t to diminish the horribleness of this incident - just to point out that what people (on here) see as acceptable attitudes are every bit as damaging.
Incidentally I know of a young adult with learning disabilities who was targeted in a city centre by teenagers last week (while she was with a carer). These things are increasing.