I’ll also tac on that when you use cloud storage, what do you think your stuff is stored on at the end of the day? Sure as shit not Bcachefs yet, but it’s more likely than not on some netapp appliance for the same features that Bcachefs is developing.
For the same reason spoken languages often have semantic structures that make a literal translation often cumbersome and incorrect, translating nontrivial code from one language into another without being a near expert in both langauges, as well as being an expert in the project in question, can lead to differences in behaviour varying from “it crashes and takes down the OS with it”, to “it performs worse”.