My Hero Academia's latest chapter ends on the major cliffhanger that Izuku Midoriya's life is still currently on the line, following the brutal battles of the War Arc. (SPOILERS FOLLOW!) There's been no peace for the heroes of My Hero Academia, even though they just narrowly survived the Paranormal Liberation Front's ambitious coordinated attack on Japan. All For One remote piloted Tomura Shigaraki's body to stage a prison break that freed the villain leader's body and some of his top lieutenants; in chapter 298 we see All For One's forces hit multiple other prisons to re-stock their ranks, while still striking at the foundations of hero society.
Meanwhile, as the villains press forward with their dark designs, we learn that the pro heroes are currently woefully understocked when it comes to able-bodied, active forces. Endeavor and Hawks are both still bed-ridden with their injuries, and while Bakugo and Todoroki both wake up, the latter has taken significant damage (both emotionally and physically) during his fight with Dabi. However, all of those ominous setbacks aren't the headlining worry: that would the fact that Izuku Midoriya hasn't ever regained consciousness, after his climactic fight with Shigaraki/All For One, in the OFA realm.
When the powers of OFA and AFO collided, All For One tried to siphon the OFA power away from Deku. However, the past users of OFA rose up and anointed Izuku as their true chosen champion, somehow exorcising All For One's power-stealing attack. Midoriya was left down and out until OFA's mysterious 4th user awakened him with the power of danger-sense (like Spider-Man). Izuku was awake long enough to try to stop All For One from fleeing with his henchmen, but afterward, he collapsed on the battlefield and hasn't woken up since.
These kinds of moments for anime are nothing new; it's practically a required staple of shonen heroes that they go catatonic at some point while access deeper reserves for their powers. The question here is: what metamorphosis is happening to Izuku Midoriya right now?
A lot of fan theory predicts that Izuku is currently undergoing the kind of process that will allow him to fully embrace the power of OFA. Tomura Shigaraki's body has undergone its own enhancement process (thanks to Dr. Garaki), and his powers have also been flexed out so that his disintegration effect and AFO abilities are now much more powerful. Izuku needs to keep in step with his rival (as they both careen toward a "Quirk Singularity" calamity), and this could be that very process we're now seeing unfold.