I've come to the conclusion that the Mor Ryde step have become so popular. Because they eliminate the stair box in the building process.
THe steps have a debris issue,they block the door way,and cannot be deployed in tight spaces.
But overall by eliminating the stair box the units are easier to build.
The steps can be a last minute attachement vs. being part of the frame assembly.
It allows the door to positioned almost anywhere which creates more floorplan flexibility. It allows similiar floor plans to share more construction techniques.
In the end they have become popular not because they are good for the consumer, but because they are good for mass production and the RV builders.