Why does whois return both valid information and an error?

Running the Linux whois command like this:

$ whois porkbun.com
   Domain Name: PORKBUN.COM
yadda yadda
>>> Last update of whois database: 2025-02-01T20:58:21Z <<<
yadda yadda
connect: Network is unreachable

The command returns the expected data to stdout, but returns a connection error on stderr. The exit code is 2. A domain not found is usually 1 and success is of course 0.

Why is this domain, and several others, returning an error despite providing up-to-date results?