I don’t agree. A lot of airlines CofC is utter tosh and doesn’t hold up in law. For example, you book long haul C but the carrier decides to swap it for a narrow body with Eurobiz. CofC will say it’s still business and EU261 won’t help, but contract law will, good faith, consumer contracts and fairness.

Direct flights are nearly always sold at a premium over indirect, even if fares have gone up a lot since booking to blur that.

If airlines could you what you propose, it’s chaos, especially at the +14 mark so no compo. This is not America so a refund doesn’t make things right.