Some home educators may home educate in a bubble. Just like some school-going parents are in their own little bubble (for example, I know plenty, those who cannot conceive of anything outside their own small existence of 9-5 in the same/similar job that their parents worked, living in the same town and going to the same place for their annual holiday and expecting that their children do the same)
Many home educated children (mine included) have been exposed to far more diverse people than they would have been had they simply gone to their local school which only draws from its local demographic (in my case, white middle class Conservative voters)
My teens' GCSE results exceed the national average for English and Maths and attainment 8. I taught most almost all of them myself. It is very possible and not particularly difficult either, from an academic point of view.
The stress/difficulty of home ed exams often comes from having the sole responsibility and also things beyond your control like exam cancellations, rather than the teaching. (And for some families, there is the stress of expense because home educators have to pay for everything themselves, including exam fees, and of having to organise SEN access arrangements)
They had lab time at a local university and geography fieldwork on the South Coast, they learned how laws are made in the Houses of Parliament and watched a live debate there, held a mock trial at the Royal Courts of Justice, learned about plants and ecology at Kew Gardens, learned about WW2 at the D Day beaches, learned about motors at Silverstone, learned about water and sewage at the sewage works... the list goes on. Plus all the fun stuff like theme parks.
None of this is particularly unusual for home-ed children. And many of these activites were in groups of 30 students.
If home educators are sometimes "righteous" (or even defensive or angry) it might be because they're dealing with the same misconceptions day-in, day-out from people who make narrow-minded assumptions that home educators are socially isolated with only YouTube and study guides to get them through a GCSE.
I don't know about how home educated children in general fare in the real world because there are no large-scale studies in the UK.
Anecdotally, most of the ones I know have gone onto jobs or uni.
There are a couple who haven't but I am not sure of their outcome would have been any different had they gone to school (they have SEN)
Equally, I know unemployed ex-school-children who seem unable to stick at one thing or hold down a job (and, as far as I know, have no SEN) but nobody blames the school (even though that perhaps is the reason).
Why is it that school hasn't failed unemployed school children but home-ed has failed for unemployed home-ed children.
Anyway, I wouldn't say that home education is better, per se, it is just different - horses for courses and all that.