It still means the weight of extra batteries is less than the weight of adding ICE. Ie the options are:
– Batteries (as per PHEV) + ICE or
– Batteries (as above) + extra Batteries

B1+ICE vs B1+B2

The value of B1 is irrelevant.

I don’t think aerodynamics much of an issue in city driving where the average speed is less than 25kpm.

This class of car is the number one seller after all and non of them really have very long range.

It also depends on the size of the BEV and PHEV batteries; the BEV's might be surprisingly small while the PHEV's could be relatively large, we don't know yet. I expect the BEV range to be fairly low due to the poor aerodynamic shape, so the less wealthy and thus more conservative target demographic in China's interior will likely favor the PHEV and ICE versions.

When this is the case I can’t see much value for anyone who can charge at home not buying the BEV (even if it is a little more expensive as the Opex will be lower and the TCO will favour the BEV).