Of course this news is terrible for him and the sport - it's crazy because it was only a few weeks ago he was quoted in the Guardian (?) article talking about WR attempts over 1500, mile and 5000m this season. Clearly that is not happening.
You really have to entertain if this is it - especially when thinking about the athlete we knew in 2023 and 2024. So he turns 26 in September and best case is back next summer season. And people will point to Donovan Brazier as a case in point as to how an athlete can now come back from what seemed like a career ending predicament, but I think the circumstances are quite different.
The biggest one is that Brazier was relatively undertrained and developed career wise before his workload dramatically increased under Julian which was the direct cause of his body's break down. My feeling is that under those circumstances it's much easier to get healthy and come back vs Jakob who has significantly more career fatigue on his body due to his development from his teenage years and also the event. You can get back to a high level in the 800 without a ton of volume, relying on your talent more than the 1500-5000 where you simply have to have volume (and in Jakobs case with his training philosophy) a high combination of that and intensity.
Wish him all the best, you'd hate to see his career end this way.
and p.s for all the kids out there wearing high stack, super soft "super" shoes for every run and workouts - especially on the track? Don't.