Some bad info here. Yes Soundsmith is MI, but the replacement is factory not user.
You're right, B&O cartridges manufactured by SoundSmith and some SoundSmith cartridges looks like the stylus is user replaceable, but they are not. ANYWAY it's factory replaced for very low cost by the manufacturer, this is a clear benefit compared to MC cartridges from some other brands.
I just checked the SoundSmith site and quickly realized all old models are gone and replaced with new design (that looks a bit weird, sorry).
An old design is better to my eyes (just my personal preferences), especially this one made for OMA.
But there are many more great MM or MI cartridges in this world (or even LOMC) new or old.