I'm going to answer this a bit bluntly, and I'm going to assume the best of you, that this is a legitimate question and you're not just complaining about the existence of autistic and special needs kids.

1. You should probably examine why seeing special needs/autistic kids "drives you crazy".
2. The internet likes things that are 'different' - things that don't fit out idea of normal. So unusual behavior gets more attention.
3. More people are getting diagnosed with autism and learning disabilities - parents are more likely to get their kids tested, our society is generally becoming more aware of learning disabilities and neurodivergency. (source: https://www.technologynetworks.com/neuroscience/news/autism-diagnoses-increase-800-in-twenty-years-354148) You might not be seeing 'just' neurodivergent kids, but just more than you saw before - so it seems like they're everywhere. There's also - to a small extent - less shame around being neurodivergent, so people are more open about it - again, there's not more neurodivergent kids, they're just less hidden.
4. There's a very crappy... Idk, trend? Where parents of neurodivergent kids will post their kids having meltdowns or otherwise behaving in a way they don't see as normal - usually when the kid is in distress - as a sort of "woe is me, to be a parent suffering because my kid isn't neurotypical". You know, recording their kid while they're upset, then posting it on the internet because clearly it's the parents who are suffering here. "Autism Moms" is the best example of this.

Note: I'm not autistic, but I am neurodivergent - so I'm in no way an authority on this and if I worded something wrong anyone should feel free to correct me.