I think this is a pretty interesting question and I agree that it's very close, but I also think in reality very few athletes could do it. I think the first thing you have to do is establish how many barriers would be on this hypothetical course. Based on the spacing for the 3000, 18 or 19 total would be equivalent. Next, what is the time cost of negotiating each barrier vs, flat running? Using the very top times (Shaheen et al), it's just over .6 seconds per barrier. So the total hurdling time cost is either 10.8 or 11.4 seconds added to whatever the athlete's best mile time is. So we're looking for a steepler with a best mile of sub 3:50, preferably 3:48-49.
If you take Shaheen's best mile (converted from 1500) he's at 3:50.4. So he couldn't do it.
Mekhissi's best mile (also converted from a 1500) puts him at 3:49.9, but even adding just 10.8 he's still just over at 4:00.7
Jager's a good candidate, with an even better mile PR than the above, but he needs to improve his technique since his current PRs show him losing .72 seconds per barrier.
Finally, I will acknowledge that there should be an argument that a shorter course with less hurdles should allow faster negotiation of the barriers than 0.6 seconds (due to fresher legs and slightly faster pace), but comparing both Shaheen's 3k WR and Mekhessi's 2k WR, the "decay" for both distances works out to the same +0.6 seconds, so if there is an improvement it won't be much.