I experience the same problem... debugging (even starting an app via debugger) on a physical device is incredibly slow for months. Since this "other" thread is locked I wanted to post my latest experience here: although my iOS devices are connected via cable to my Mac, I just by "accident" disabled on my iOS device's active Wifi settings the "private Wifi address" switch and all from a sudden debugging and all stuff runs fast again. Even after turning the private wifi address switch back on again, it's still fast to deploy and debug from Xcode (via cable). Perhaps this can be a workaround for someone else as well...