dovecot - Aug 2020 - About the changing namespace handling from v2.0 to v2.1 or later

Hi, all,

Please tell me about the patch and description below.

 
https://github.com/dovecot/core/commit/5f46b863383fc94afcd2693ecae8788cb5fdd20c
  example-config: Use a default uncommented "namespace inbox".

  https://doc.dovecot.org/configuration_manual/namespace/
  There's a default inbox namespace added in 10-mail.conf. If the
configuration doesn't explicitly specify a namespace (as was in v2.0 and
older) a default namespace is created automatically.

Since v2.1, namespace is enabled by default in 10-mail.conf, and
"inbox" is added as a sectionname of namespace.
I checked the dovecot's mail archive, but I didn't understand the reason
for the change.

Please tell me about followings.

 - Why "inbox" was added as a sectionname?
 - Why was namespace changed to be enabled by default?

Best regards,
MIZUTA Takeshi