Earlier quoted context omitted.
They don't break a letter of the law (probably), but they break spirit of the law. Laws do not exist like a puzzle challenge to be beaten by clever lawyers with a reward being factual exemption from the law. They are usually intended for everyone.
Most of the criticism (of Nike and Apple, for instance) isn't for breaking even the spirit of the law. Most often the companies are acting precisely as the law is intended to work, and criticism is based on a misunderstanding of what is turnover and what is profit, and how taxes should be calculated. Very commonly the complaint is that Nike (for instance) pays no corporate income tax to a country even though it sells…
A taxation race to the bottom is not what the fundamental principles of the EU are about. At best they are an unwanted side-effect.