I think it's fine for a conceptual understanding. The Go runtime looks a lot like an OS, mapping G (goroutines) to Ms (worker threads), removing goroutines from the workers when they block in syscalls, waking up goroutines when a lock they want is available or a syscall finishes, etc.

In the end it really depends on what you think of inetd as. If you think of it as "I install this one server and now I have finger and gopher!" then that seems similar to Caddy's applications. If you think of it as "whenever a TCP connection arrives, the fork() syscall is used to create a process to handle that session, file descriptors 0 and 1 are connected to the TCP socket, and then exec() according to the global config is run to handle the protocol", then ... no it's not the same as inetd.