He does not post on social media a dozen times a day (almost never on twitter, every week or two on the public facebook page, every few days on instagram), and in any case this sort of thing would not be consistent with most of his other social media posts. There's some friendly stuff and I think one picture of him out of a firesuit, but it's mostly stuff that promotes the "brand" or the sponsors. Entirely normal from a sponsored, professional athlete.
A pro football or basketball player couldn't get away with keeping radio silence on an injury like this, but Bryce can and I have no problem with him not broadcasting personal health news if he doesn't want it out there.
It was rare that he'd go a day without posting an Instagram story, but has been silent over the past few days. He normally does as really good job of updating people on what he's up to (he posted the day after he broke his back). Just a strange series of events that everyone has been radio silent on this.