That's an impressive payload (sts), but it's not always about the size of the sensor. These aren't bombs, these are intelligence platforms. Bigger and better cameras (especially film cameras) were the sensor of choice during the cold war when strategic intelligence reigned supreme, but tactical intelligence is a whole different animal.

Sometimes what the COCOMs need is persistent SA that may or may not be imint. There is usually value in the traditional imagery analysis after the flight's over, but in today's wars the decision-makers more often need to know what's going on right now for days on end. They all have their place, but it's usually about the right tool at the right time, not the biggest tool for a short duration of time.