The "exposure" of the top intake from the frontal aspect isn't as important as whether the path of the intake to the engine face is suitably serpentine and obscured, and based on the positioning of the top intake, the geometry of the airframe, and the positioning of the engines (from all the other pics we have of J-36), it should be suitably quite entrenched indeed.
The metal middle frame in the canopy isn't necessarily a big deal -- after all, J-20S as a twin seater has an "exposed" metal frame between the front and rear pilot's canopy glass as well. Not to mention of course, B-2, and B-21 both have very significant "exposed" frames between their canopy/cockpit glass panes.
If anything, J-36's relatively small middle frame between the left and right canopy glass just goes to show how huge the canopy for this aircraft is for both of the pilots -- which will offer much more visibility than say, on B-2 or B-21, which is to be expected given J-36's role is primarily A2A, and being able to achieve as much Mk1 eyeball visibility as practically possible is still beneficial even for future aerial warfare concepts.
