Back in my individual contributor days I got into serious trouble because of this. Where can I find it has officially been deprecated? I tried and I can still use it without getting any warnings?
It’s a shame how Apple proceeded in your particular case. But your app JSBox has let users run “apps” by-passing Apple’s review process, like a NES emulator that created and shared yourself. This converts your app in an eco-system within iOS which is against the guidelines.
Hope your account and your apps are brought back to normal so you can fix any irregularities and continue doing a great job.