Ipc\connect is not part of the IpcHub interface
This essentially makes the entire IpcHub interface useless, as custom IPC implementations (i.e. IPC over FIFO, IPC over shared memory, et cetera) cannot override the logic of Ipc\connect() without also uselessly reimplementing the ProcessContextFactory and process-runner.php.
The socketConnector can of course help, but again, it is not used by the default runContext logic, requiring copying a large amount of logic
The connect function doesn't make sense as part of the IpcHub interface (well… maybe as a static method). Rather it sounds like what you're looking for is a way to override the connection logic in process-runner.php.
Potentially an IpcConnector interface with a global instance which could be overridden by a bootstrap file specified on the command line, similar to what we did for workers.
The bootstrap file would be the most versatile solution, allowing any setup to be done before attempting to connect to the parent.