It's the wording that needs banning/that ad rather than the model.
I agree with this. The model, while quite likely in possession of surgically or digitally enhanced breasts, is not necessarily too thin.
There are all kinds of bodies – you can see my ribs and I eat very heartily and very well – and so the idea that there is only one acceptable 'beach body' needs stamping out.
As an aside, treacle, I have over the years received and still get plenty of insults and discrimination about being thin –people assuming I'm anorexic, telling me I need to eat more, names like 'skinnymalink' and 'lanky piece of shit'...
I know people insult fat people too, but it's certainly NOT limited to fat people. Again, it's all part of the idea that women's bodies are there to be examined and commented on.