User, my mother and her siblings born before widespread vaccination programs began. They all caught measles - 3 recovered one died of complications of measles at the age of 9, a number of months after contracting it.
On my fathers side, my grandfather had long term problems after polio, and my fathers sibling had encephalitis and was left with complete deafness in one ear after measles (I know a woman in the same small village who was left completely deaf after catching measles only a couple of weeks before, in the same outbreak.
These were people living a healthy, active rural life with good food and plenty of sunshine. They still, unsurprisingly, caught easily transmissible diseases off their friends and relatives, because transmissible diseases are transmissible!
People who don't vaccinate are benefiting from herd immunity to reduce the chances of their kids getting these diseases while at the same time increasing the risk of outbreaks. No vaccine will give 100% protection to everyone but if you are unvaccinated then you have no protection.
Go and look at the graveyard from pre about 1950 and look at the number of babies, children and young adults listed on family headstone. Many of them died of vaccine preventable diseases. THAT is why you should vaccinate.
I remember my grandmother saying she was first in the queue to get her surviving children vaccinations when they were made available. People queued, she said, because every parent knew of family members, friends, neighbours, who's children had died of these conditions, sometimes several in one house. And it wasn't just the deaths, far more children were left with life altering damage (for each death, many damaged). Brain damage, irreversible heart damage, lots of deafness, crippled limbs (all at a time when there wasn't much you could do about any of that).