Your analysis is deeply flawed because you’re comparing the last 1600 meters of 5,000m championship races that were very different.
1) Bekele ran the first 3,400 of the 2008 Olympic final in 9:00. Jakob crossed 3,400 in this year’s world championships final in 9:17. That’s a huge difference when looking at their last 1600!
2) Bekele was front-running his last 1600. Jakob was drafting behind others.
3) It’s not just about the last 1600. We should look at the last 2,000. From 3,000 to 3,400, Bekele ran 59.96! Jakob’s split for that segment was 62.55.
4) Jakob had super spikes. Bekele did not.
Add it all up, and we have Bekele front-running his final 2k in 4:56.97 in regular spikes after hitting 3k in 8:00.85. Jakob ran his final 2k in 4:56.69 in super shoes while drafting behind others after hitting 3k in 8:14.61. Bekele’s run was much better.