The problem with marathoning in the US is that the wrong people are running them - old over the hill runners like me. The young guys aren't, and too fix this you have to understand the mentality of the college runner.
Most college runners never run at all after. Why? Sure, much of it has to do with life pressures and the like, but we had those same pressures in the 70's.
The big problems is that college guys all want to "do something" great in college - it's their only chance to make a mark. So, the set goals like "being conference champ" or "making all-american", small-time stuff.
I think "making the olympic trials" could be another one of those "big things", but 2:22 is damn freaking fast. Some college guy computes the splits and knows that they would have to train their ass off for a few years just for an outside shot at the OT. It's too far off, and the chance of success is too slim for the work required. Therefore, the marathon OT is not even on the radar for college guys, and they quit running before they ever seriously consider the marathon.
Now, if you make 2:30 the standard, now college guys will have to make the mental decision, "should I keep running 70 mpw and try for conference champ, or should I bump my mileage up for a while to get to the OT. The compute the splits need to get to the OT, and it's reasonable if they put in a year of big mileage. AND SOME OF THEM MIGHT BE GREAT AT IT. We have guys capable of being great marathoners, problem is they never try the distance. A 2:30 standard would increase participation in the marathon by college guys SUBSTANTIALLY!!!!! Try it for the next OT.