Ryanair has a clear policy on passports
It is quite plainly stated when booking that a passport is a condition of travel. Those who fly regularly to the UK will be aware that occasionally on arrival British airports will run an ID check on all incoming passengers. A passport is required for that, and on return to Dublin airport there is a passport check as well.
We don’t have national identity cards and, for the moment, passports are the safest and most secure way of identifying who is flying.
