(the oddity being the Roadtrek 210 which left the factory as a van, and Roadtrek cut off the van body - leaving the doors - and added a wider body. Not sure if anyone else ever did this)
Ah, the old A, B, B+, and C debates.
Pleasure-Way (Excel models) and others cut off the van body for years. All Bs.
The actual oddity may be the Roadtrek 200 built on a cut-away chassis. It looks like a B and quacks like a B but would be a C according to the RVIA definitions.
I think the B+ has established itself. Most know one when they see it regardless of the RVIA definitions. It's not hard to define and has been done so many times on this forum. Regardless of how the B+ term originated, the RVIA definitions should be updated. But whether they are or are not would make little practical difference, except perhaps to reduce debate. It is what it is regardless of what it is called.