Something must have changed in meantime (updated openssl or something) as I cant reproduce:
pi@noads:~/tmp $ openssl req -new -out pi.hole.csr -key pi.hole.key
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
Country Name (2 letter code) [AU]:
State or Province Name (full name) [Some-State]:
Locality Name (eg, city) :
Organization Name (eg, company) [Internet Widgits Pty Ltd]:
Organizational Unit Name (eg, section) :
Common Name (e.g. server FQDN or YOUR name) :pi.hole
Email Address :
Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password :
An optional company name :
pi@noads:~/tmp $ openssl req -text -noout -in pi.hole.csr
Subject: C = AU, ST = Some-State, O = Internet Widgits Pty Ltd, CN = pi.hole