Bronny has been apparently getting a second opinion at Mayo Clinic and is a long way from resuming any sort of basketball activities (if he ever does). I got a bit worried when people said he could be back in a week or two but glad to see they are getting extensive medical tests. His life is so much more than basketball
I would be amazed if that happens. A cardiac arrest isn't something you just shrug off, even if you are very lucky and they restart your heart within a minute or less. There's all kinds of damage that can happen when blood stops flowing to your brain and other organs. The quickness of his recovery will really depend on what caused his cardiac arrest. If there's an underlying medical issue that caused it like coronary heart disease, heart valve disease or some kind of arrythmia then the odds of him ever being able to play again will lengthen, because the risk of a repeat episode might be too great.
But if it's treatable, or it's something like commotio cordis where it's caused by external force hitting your chest like what happened with Damar Hamlin or Louis Acompora, the high schooler whose death after being hit in the chest playing lacrosse in 2000 led to New York passing a law requiring all schools to have AEDs, and there's no underlying heart condition, then he should eventually be able to come back. As Moranis said Vince Iwuchukwu suffered a cardiac arrest (also at USC) and returned seven months later. Christian Erikson, the Danish soccer player, suffered a cardiac arrest in June 2021 playing for Denmark against Finland at Euro '20 in Copenhagen. I was watching that game, it was eerily similar to what happened to Hamlin, they had to resuscitate him on the field. They called off the match and resumed playing it in the evening by which time he was awake in hospital. After having a pacemaker installed he was able to return to play a year later.
So it's certainly possible - just depends what caused it, how much damage he suffered and what is the likelihood that sports, including the risk of contact, causes a recurrence.