It's called goodwill to your customers, something which you and your employer are not prone to and long term will harm your business as people go elsewhere where they can. Customers do not like small print.
First and foremost I'm not an employee of Ryanair so get down off that horse.
Secondly whether customers LIKE T&C's are not is irrelevant. Airlines are required to have them and state exactly what is included as consumer advocates are very quick in highlighting that something is not included.
The idea that its goodwill not to charge customers additional when Govts change taxation is laughable as proven by the events in 2006/7 when UK Govt added in an APD and Airlines collected it later.
Not aware of many people not choosing to fly since.