It's Ryanair, this is nothing.
For every decision they take they always consult the Big Encyclopedia of Dark Patterns and Asshole Design™ to maximize the damage to the user
Probably they noticed that a virtual gift card will get used very soon (example give the money for a trip to someone else) so they are going to charge extra for the "convenience" while the physical because arrives weeks later via snail mail gets forgotten and they can keep the unused credit at expiration.