One thing is the approach, constructed by the authority, having in mind not only 737s and A320s but all the other types that will probably use that airport as well. The other thing is the aircraft capability. Both 737 and A320 can fly RNAV approaches fully managed/IAN, and it doesn't matter what the approach minimum is based on. One has just to be aware how to use the minimum in low temperatures and which one to use in which situation.
If you have the approval you can fly all approaches in APProach mode on the 737 using IAN, depending on FMC setting either as precision approach (ILS/GLS/MLS) or NPA (all the rest except RNAV RNP (AR)).
For example the EDDB RNAV (GPS) 07L has a Baro VNAV minimum of 490 and a LNAV minimum of 630. The Baro VNAV is available down to -15°C, below that you cannot use it anymore and have to use the temperature corrected LNAV minimum. Yet the approach can be flown using the same procedure, it is the same approach after all, just different minima depending on aircraft equipment.