The EU really isn't a single large market though for most practical purposes. For the purposes of complying with regulations and accepting payment it is, but for every other practical consideration that matters to a company doing business there, it's a few dozen separate markets.
Global market share hardly matters though. UN isn’t regulated monopolies national agencies/EU are. Not that it should matter it’s still an oligopoly which is not that different
The EU is arguably the biggest market in the world, why wouldn't it use that for the benefit of its citizens? Same way Apple uses its weight to cut better deals with its providers and the countries it operates in.
The problem is that EU cannot be considered as a whole. What you see in particular markets can largely differ one from another - what you have in UK, doesn't apply to France. What you have in the latter, doesn't apply to Germany, and so on...
The market they're interested in is the EU. So "all over the world except China" includes the EU. Defining the market as the region the governing authority has power over is nothing new: The FTC rules on the US market, the European Commission rules on the EU market.
Market doesn't mean advertise, it means to bring products to market, so yes, bringing products to market for the world is also bringing them to market for the EU.
The EU assumes you have a market-dominant position at a market share of 40%. You don't even need a majority of the market to be treated as a "monopolist".
The EU has a similarly sized internal market, but it's consistently self-sabotaging on many levels (EU, countries, state, local) so does not realize a lot of the benefits it could get.
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