The article discusses several issues with macOS 10.15 that cause noticeable delays and stalls, including notarization checks, privileged file system locations, keychain access, and application launch delays. These issues can be mitigated by disabling internet connectivity or System Integrity Protection. The author reports that Apple has responded to these issues, stating that they are 'by design'. The delays are caused by synchronous network activity before returning to the caller, which can be a concern for both privacy and speed.