No. There's simply too many leak spots like edges, the fans themselves, slots in back, unused ports etc and pc fans do not have the capability to increase 'pressure' to much degree.
If at sea-level, air pressure is 14.7 lbs/in-Sq. Inside a 'positive pressure' pc with fans at a constant rpm, you might see 14.71. In a 'negative pressure' pc, you'd be lucky to see 14.69. Seriously not much difference. The only thing this really affects is the micro-particulate dust that's approximate to the case. Positive pressure blowing enough air out of the cracks to move the dust, negative pressure pulling it in unfiltered.
But trying to maximize this by opposing fans with intakes on top and bottom and front creates hotspots as air is now no longer flowing in-out, but circulating inside the case
Front - intake
Bottom - intake
Rear - exhaust
Top - exhaust.
Unless otherwise directed by case design.
You have a gpu exhausting hot air, that's climbing the side of the panel. The rear wants to take that heated air, bend it 90° and shove it out. You also have a top fan blowing air in, confusing the heated air from the gpu and circulating it around the case.
While immediate temps might look good, try heavy gaming for an hour and shoving increasingly warmer air back at the gpu....