TL;DR: R-Type Dimensions III is switching from a Game Key Card release to having the full game on the card. Because of this, the physical release MSRP is increasing by €10. They will honor the old price for existing pre-orders.
Initially, the publisher said that this was made possible by the new smaller capacity cartridges that Nintendo just announced. Later, they updated the press release to remove any references to cheaper cartridges and instead said that Nintendo did not announce anything.
They could just have made their digital sales resellable and done without the key cards entirely. But of course they won’t, because why would you accommodate your customers eh?
If they don’t have to, they won’t. It’s not like their competitors are any better.