It doesn't appear that this is what was happening here. They did the deals in London and then claimed that they were done in Ireland for tax purposes.
Essentially, they expected that no one would ever check whether a tax nexus was established in the UK. The fact that the UK didn't have any ability to check if this was true doesn't mean a law wasn't broken.
A paywall mysteriously went up so I can't go re-read the article. But IIRC the article accused Google of avoidance, not evasion. Avoidance is legal and evasion is not. So the article seems to be saying that closing deals in Ireland to avoid taxes is legal, or at least likely to be legal.
This is england. We have strict libel / slander / defamation laws.
Saying that Google is avoiding tax is fine. Saying that Google is evading tax is not fine unless I can prove that they are.
Note that "tax avoidance" used to mean normal "tax planning" - using purely legal means to reduce your tax bill. Now it feels a bit different. Now it feels a bit sleazy, a bit of a grey area, a bit borderline. When people say "tax avoidance" it feels as if the steps taken are right on the borderline, or are loopholes that just haven't been closed yet.
Tax avoidance has evolved into a shell game of jurisdiction shopping and regulatory arbitrage.
In the USA, states got so fed up with companies assigning their trademark and copyrights to DE subsidiaries they could make tax-free royalty payments to that they started doing combined reporting to nullify the effect of those constructions. Even though companies had no offices, employees, or business in DE, they nonetheless were claiming that their very valuable IP was situated there.
The net effect is that it's easy to deduct royalty payments in a high tax state and have them appear in DE, a low-tax state.
Not to be undone by combined reporting, they've (companies) now expanded this approach to offshore destinations to keep the benefits of transfer pricing. GOOG does it. AAPL does it. MSFT does it.
Essentially, they expected that no one would ever check whether a tax nexus was established in the UK. The fact that the UK didn't have any ability to check if this was true doesn't mean a law wasn't broken.