I am recognised ALL THE TIME! I name change quite a lot. Mostly for fun, and then also to throw off people who don't know me, as in, I wouldn't want randoms to start piecing my posts together and then to follow me out of interest! But I write in a similar way every time really, so my friends and family usually spot me and message me to say 'is that you?!', then we talk about the responses!
Anything I post about I've spoken to them about a gazzilion times in detail, so there is nothing new. I mostly post about myself, but when I have complained about someone, to be honest if they read it and recognise themselves it might help them with some reflection? I have read bits once or twice on here posted by two people I know and I changed my behaviour as a result, as I didn't realise I was causing an issue for them, and it was nothing for me to just stop that.
It would be great for to people to just communicate more transparently, really, then we'd all have fewer hang ups and everyone's mental health would be far better because we'd see how similar we really all are.
I'm not a huge poster, I can't come onto mumsnet as much as I'd like, but I have seen some similar names post about similar issues (DV, childhood trauma etc), and so conversely, sometimes seeing the same name pop up makes me sad that the person remains so traumatised, but I never say anything there.