…so I still do not understand why the generics makers care much at all about non-sub biosimilars. All told it looks like, perhaps, $4-8B spread over 10's of generic manufacturers in 6 or 7 years.
When mAbs come into play, the numerator will be considerably higher than $8B, IMO, and the denominator is apt to be considerably smaller than 10 (companies). Hence, the interest in non-substitutable FoB’s is not irrational.
The fallacy of composition applies, of course. Commercializing non-substitutable FoB’s can be a decent-sized business for a few companies; however, if every company with the capability to do it decides to do it, it will end up being a bust for most or all of them.