Its something to do with directing airflow into the engine at high AoA's rather than it just flowing up and around the fuselage, but I'm not
familiar enough with the technicalities to go into detail I'm afraid. The F-16 has a similar arrangement.
Same reason the F-16, Global Hawk and many, many others sepatare the intake away from the fuselage, so the intake ingests undisturbed flow. Take a
look at most modern A/C and you'll notice the same, undisturbed or at the least laminar and evenly distributed flow, is a very good thing for the
compressor face.