I keep writing posts and MN eats them!
Anyway, socialisation in school really isn't the be all and end all, and IME the people who bang on about it are those who don't really understand, or those who were amongst the few who positively thrived in school.
Some children do really well, make friends easily.
Some children find this difficult.
HE is not socially isolating at all, or in my case, is done at my sons' pace (both have ASD), so is far more fulfilling than enforced association in school ever was, and when you do socialise it crosses age barriers, abilities, there doesn't seem to be the competitiveness that there is in secondary school, there is more scope for modelling kind, thoughtful behaviour, and children with differences are more likely to be included, rather than ostracised, as so often happens in school.
Even if a child has no SN, I think this kind of environment can be hugely beneficial, as they'll be more likely to learn to treat their peers with respect, something which I believe school, particularly secondary, does not do well (and I say that through personal experience, plus the experiences of my sons, and those of many people I have contact with).
There's an assumption that children will come out "weird". SN and children who struggle to fit the system are over represented within the HE world, as eyre less likely to thrive in a school environment, so those considered weird having been home educated are likely to have come out of school perhaps performing normal a little better, but are often utterly broken by their experiences.
For a lucky few, school days are the best in your life, for most people it is something to be endured, or something to recover from.
If you can HE, and you're ok with lack of time to yourself (something I struggle with), then I believe it can be a very valid choice.
I'm not an over zealous home edder, I actually wish my sons had been able to cope with school and be amongst those who enjoy it, and I do feel we are HEing out of necessity rather than choice, but it's not the doom and gloom that lots of people think it is, rearing weird, anti social hippies. It's about having the freedom from the increasing pressure put on our children in school, and for us, a way to limit and soothe the awful mental health issues that were created within school and the social structure which so many hold to be vital for children.