Like others have already said I think the hostility against anti-vaxxers has become stronger because those diseases we thought we had eradicated (or made weaker) seem to be having a surge again. The children who weren't vaccinated aren't joining that 'herd immunity' which means they 'could' be assisting in the spreading of the diseases.
Of course it's a valid worry that holds back parents from vaccinating. There are children out there who are vaccine damaged. Just as there are children, as previously mentioned, who developed meningitis and had both arms and legs amputated. A quick google search pulled up at least five children that lost all limbs to meningitis - three were children under the age that could be vaccinated. That's where the herd immunity comes in. Those children may have been more protected if those who could have vaccinations, had actually all had them.
But it's no good berating a parent for trying to do the best, as they see it, for their child. It's about informing people, trying to have a sensible debate and listening to concerns. My sister refused the MMR vaccination as her DC was born about the time that discredited link to MMR came out. She managed to get three separate injections done instead by going privately at the time. But that sort of thing needs to be available. Some parents don't vaccinate because they feel 3 in 1 or 6 in 1 is too much - I prefer one injection, less pain. But that's my preference. I'd prefer parents who feel it's too much to be offered 6 separate injections for their child than not be vaccinated at all. And I know all the arguments that parents may forget the 2nd one or whatever. But we get texts to remind us of our appointments now - it's not hard. Better that risk of missing a jab and listen to the parents who worry about this than brand worried parents 'idiots'.
Our GP surgery, if they see us around flu jab time, ask if we've had it and give it to us if we haven't. Our DS has a heart condition so we all get flu jabs to give him umbrella immunity as well as having his own jab. That's an easy one for a GP to say 'oh, I see you missed little Jane's 2nd jab - OK to do it now?' when you take the child in for a check up.
We were all vaccinated as is our DS vaccinated as my family has had a direct death due to no vaccinations being available. My 'would be' aunt died in the 1930s due to diphtheria. She got it from sharing a lolly with her best friend - who was a carrier (not everyone who gets the diseases shows the symptoms). My aunt died, aged 10 years old, because a vaccination wasn't widely available and no NHS in those days.
My mum tells the story of the GP running down the road after he had the results from a throat swab on my aunt. He was shouting 'get the children out of the house - it's diphtheria - get them out now!'. It is that dangerous and that contagious. My mum couldn't go home for two weeks. She stayed with a neighbour.
My aunt died two weeks later, a few weeks before her 11th birthday, unable to swallow and with her neck and shoulders paralysed. An agonising death and my mum had us all vaccinated because of it.
Diphtheria is spread by sharing food, cups, etc (everything kids do) so can't be easily avoided. Without enough people having vaccinations it will be on its way back - you really don't want it.
God knows how that poor little friend of my aunt's felt. Imagine living in the same road and knowing it was traced back to you (GP did tests on everyone and it turned out she was a carrier). My mum's family never blamed her - obviously - it's not like she deliberately played with my aunt knowing she was unwell. But I would imagine it hit her at some point as she grew up and that's hard.
But calling people idiots helps no-one. Making it easier to get single jabs, education, listening and discussing is the way forward but everyone (anti-vaxxers and vaxxers) have to have an open mind. Dismissing anecdotal information (like the mum of my son's friend who is deaf in one ear and has SEN which was directly linked to German Measles in childhood. She was developing correctly, hitting all milestones before she contracted it) is as bad as saying anti-vaxxers are idiots. My friend's life is a very different one from the one she may have had if she hadn't contracted German Measles...
Sorry for the long post but these seemly 'innocent' diseases are only innocent because vaccines have weakened them. We don't want them at full strength again.