No, by being anti-competitive. Most countries have laws against monopolies, and it was naive to expect that countries would wait until you destroy the competition to enforce those laws.
They have less than 25% smartphone marketshare. What monopoly do they have?
That's why the regulation targets "gatekeepers" with revenue in the billions and at least 45Million European users.
The EU decided that this is large enough to be limited in what they can do.