So asking how much tax is paid or how much supply chain is in the EU doesn't necissarily make sense here.
The idea is whether the company has some loophole where the profits are registered in some offshore island in order to avoid taxes, as well as how big part of the product is actually made in europe as opposed as in X non-european country. I have seen a lot of products advertised as being products of the native country when they are actually rebranded chinese products or whatever (I have no issue with chinese products, but if the point is to know which products are european products this is important information).
High-level discussions rarely go down to this level of detail, and from the point of view of the consumers it is not very relevant. What matters is coupling with the US or China, and the relevant regulations.
No it isn’t because the UK is not in the EEA or the single market.