My definition of 'scrapped' differs from theirs: they aren't getting rid of the scanners altogether, they're replacing them with an upgraded model. OK, the upgrade gives them privacy features, rather than raw images, but 'scrapped' seems a bit strong.
I should also note that it's only Manchester airport that's affected, not the whole of the UK.
The normal definition of scrapping something is to get rid of it, typically in such a way that it is not reused in its current form.
e.g. If I scrap my car, it means that I am no longer using it, nor have I sold it on to another driver to use it. It will likely be broken up for parts.
Whether I get a new car to replace it has no bearing on whether it has been scrapped.
I should also note that it's only Manchester airport that's affected, not the whole of the UK.