I don't think people appreciate the value of equality until they realise that it hasn't always been that way or even at all similar to today. I know many young women who know they would have had difficulty getting jobs in most fields say 30 years ago, but are shocked when they find out that they would have been expected to give up most jobs on marriage, wouldn't be able to have a loan in their own name, could be legally raped by their husbands, etc etc.
I think children need all sorts of literature - stuff that encourages them to aim high and provides role models for behaviour, that feeds their imaginations, that teaches them vocabulary, how plots work, and have the structure of a good story, and also stuff where the subtext values are in accord with the overt values. Blyton does OK in all but the last, but as a child I never noticed all the times when a 'good and kind' character was patronising or dismissive to someone of another background. All I noticed was the Five being willing to hang out with Gipsy Jo and the circus folk and so on and stating that such people could be kind and generous, and totally missed the subtexts about them using dirty rags or not being trustworthy and digs about poor spelling.
Ironically one of the books I won't be putting in ds's reach even when he can read it is 'The Six Bad Boys' which was considered very ahead of its time with six boys (!) who for a variety of reasons have family breakdown and end up in the youth court. The blame is placed mainly on the parents of both the middle-class boys and the working-class ones, but also made clear that circumstances can affect such things - one boy's family who had 5 kids and parents living 'in two rooms' get transferred to a new housing estate and a nice little house and live happily ever after once they're not overcrowded, one's mother wasn't coping with being abandoned by father and received help... but one got packed off to Borstal despite being regularly beaten by his grandfather - he was Irish so there was no hope for him... Apart from the amazing anti-Irish sentiment it's very forward-looking for the time -you could have it serialised in the Guardian even today!
'The Put-Em-Rights' is another one where wealthy kids are inspired by a preacher to help others who 'need' it and have it brought home to them that actually fixing their own faults would be an idea first - and the working-class boy who tags along learns he should be happy with his 'equals' not his 'betters'.
Both are fascinating social studies but don't contain adventure or imagination for small children, and certainly not enough to counteract the subtextual messages.
Forgive me for not being very coherent today - I'm off my face on codiene...