The diagram shows a singe MBJ in a trough just ahead of two service disconnects. While 250.24(B) requires instead 2 separate MBJs, one in each service disconnect, I would argue that the arrangement shown should be allowed.
If the trough and two service disconnects are instead all one enclosure, then 250.24(B) Exception 1 would allow a single MBJ. (*) So I don't see it much of a change to allow the diagram in the OP when the enclosures are adjacent to each other. Also, if the source were a separately derived system, with the transformer in place of the trough, the arrangement would be allowed as shown (except the jumper would be called an SBJ instead of an MBJ).
Having a single MBJ will reduce the risk of neutral current on the EGC system. When there are two separate MBJs, you end up with two separate EGC systems. If those EGC systems are ever interconnected downstream, as seems it would often be hard to avoid, there will now be neutral current on both EGC systems.
Cheers, Wayne
(*) If the trough can be joined to the service disconnects in a way that would create "an assembly listed for use as service equipment," then the diagram in the OP would be allowed. But I think that exception envisions a single overall enclosure.
