IsItMeOr, I am no expert either, and yes, I agree, and that's why I said the basic tenets 'remain largely the same'. I think we have just settled into a less formal, less proscriptive way of grammar and syntax, nevertheless there are limits, and lows to which some us refuse to sink, such as 'we was' and 'I done'. If we allow ourselves to become too casual our language will cease to make any sense at all.
However, in this instance I do feel strongly that the root of the 'haitch' problem lies firmly in the wrongly held assumption that people who say 'aitch' are dropping the 'h' sound, and are therefore being a bit common. They say 'haitch' because they think that to do so is to speak 'nicely'. There's no shame in it - to try to get something right (even if you are misguided) is a good thing. So many people do drop their aitches that it is a perfectly understandable error to make - but still wrong! So no need for people to get all shirty and defensive and play the race/region/class/privilege(or lack of)card when it's pointed out to them.
Hypothetically, if certain socio-economic/regional groups habitually dropped, let's say, their Ms, then people who wish to speak well, and sound educated would no doubt refer to an M as a MEM. It's common misunderstanding, that's all, and no grounds for changing the entry in the OED, any more than it would be right to change the word specific to pacific, just because a significant percentage of the population can't seem to get to grips with it! Where do we stop?