Humans spent thousands of years living very different lives to how we're expected to live now. The modern world only really suits a certain type of person and everyone else can fall by the wayside. Employers want automatons with perfect health and permanent smiles plastered on their faces and anyone else is discarded. Life's always been tough, but at least the human inhabitants were more or less suited to their living and working circumstances.
I think many people want to get off this merry go round and, rightly or wrongly, poor health is a way out. Many young people don't seem to want to participate in the world because life isn't all fluffy rainbow cloud shaped and super easy and comfortable.
On the other hand, adhd cuts life expectancy and can lead to addiction, violence, crime and suicide. Autism leads to earlier death, poor health and suicide. The world is getting more neurotypical and even bog standard introverts are struggling now. The world is run on noise, stress, cynicism, unpredictability, hostility, suspicion, cruelty, isolation, dog eat dog, violence and treating people as disposable, so it's no wonder people are finding it scary. It's been about 200 years since the industrial revolution and 200 years of people being employed chewed up and spat out and the cracks are gaping chasms now. Perhaps the people coming from abroad to make their lives here might be able to put another 200 years of toil in to keep the rich in money and keep the country ticking by whilst us and our hapless offspring shrivel and die on the vine.