This article mentions very little of what could actually be wrong with a Ruby implementation (I recall one point about how Ruby on Rails tends to guide developers toward particular solutions). It describes mostly problems that are completely independent of Ruby and would happen in any migration.
Theirs failed because they didn't plan well. And some of the "work" they mention to undo the migration isn't unique to Ruby either (e.g. obviously in any new system, if features are added that aren't in the previous system and users/data grow dependent, you might have to retrofit your old system with the new features before you can smoothly move back).
Theirs failed because they didn't plan well. And some of the "work" they mention to undo the migration isn't unique to Ruby either (e.g. obviously in any new system, if features are added that aren't in the previous system and users/data grow dependent, you might have to retrofit your old system with the new features before you can smoothly move back).