Enforcement of EU261/2004 in UK/ Ireland/ EU26
I would suggest it is very very patchy at best and non-existent at worst; with the latter being the median enforcement position.
I seem to recall when I followed another website (since disappeared) concentrating on a pan European overview of this issue, that there were some slight indications of serious enforcement attempts in some Nordic country/ies. Denmark, perhaps. But broadly little if any serious interest.
Certainly I can recall an attempt personally here in the Kingdom of Spain about 7 years ago to get some leverage from the Spanish CAA over a short notice cancellation by a Spanish registered carrier. To describe to reply received as unhelpful would be to err on the side of generosity. Wildly so, indeed.
To the present:
If this attempt at enforcement by the CAA on Ryanair, certainly the biggest single-brand carrier in Europe is to be taken seriously, and I would suggest that the jury most certainly is still out on the issue, then wonderful.
And of course sauce for the Irish goose is sauce for the Spanish gander. And all winged species in between, irrespective of domicile.
(I note an inference in an earlier post to the effect that US airlines are de facto exempted from enforcement action under these provisions. Can anyone confirm?)