Apple has announced that they are starting a transition to a new architecture called "Silicon" which uses the new M1 computer chip instead of an Intel CPU.
Pixologic will be providing native support for the Silicon platform. However, we do not yet have an ETA regarding when our software will be able to run natively on it.
For now, you should be able to use Compatibility Mode to allow ZBrush to run.
Please see this article for more information.