The length of the intermediate approach segment shall not be ... less than 9.3 km (5.0 NM)
To fit a least the minimum I.A.S in tight airspace, obviously, the final segment might need to be shortened. OP suggested already,
More towards the question asked:
Originally Posted by Chapter 5 FINAL APPROACH SEGMENT
5.1.3 The final approach segment should be aligned with a runway whenever possible. All final approaches with a
FAF have an optimum length of 9.3 km (5 NM). The minimum final approach segment length shall not be less than 5.6 km (3.0 NM). This value also applies to the minimum distance from the FAF to the threshold except for non-RNAV procedures constrained by existing installations. Exceptions apply
Personally (EU roots, busy hubs) I found 7, or even 9 NM more convenient. Most probably that SOPs had been built around those. One idea left at the moment = noise footprint.