Google must really benefit somehow from the change, otherwise they could leave it until much later in the year, and see what (if any) changes Parliament makes to privacy and data protection law in the UK.
And that assumes that the transition period is not extended. (Which it doesn't seem likely to be, frankly).
LinkedIn is Microsoft, which should also be included given it's scale. It should be FAMANG.
Also, the FAANG expression didn't start around scale, if that was the case netflix wouldn't have been included as early as the expression was coined. The expression was about developer compensation. That seems to have changed recently(-ish) though and now the expression is more like "unicorn" instead of just the specific companies that make up the acronym.
(EDIT: That would indeed be Apple and Netflix, as hinted by another comment).
And they probably do that for everyone only because it doesn't eat into the main profit generators in their business models. Not many marketers paying Netflix to advertise their new natural soap line to targeted prospects I'd imagine.