[15.0, 16.0] Removed mail default "From" feature? (params: mail.force.smtp.from, mail.dynamic.smtp.from)

Impacted versions: 15, 16

Documentation doesn't match the Odoo implementation/code anymore, since version 15.
This isn't an issue (ignore) for version 14, 13 (and maybe earlier).

According to documentation:

• version 15: https://www.odoo.com/documentation/15.0/nl/applications/general/email_communication/email_servers.html#use-a-default-from-email-address
• version 16: https://www.odoo.com/documentation/16.0/nl/applications/general/email_communication/email_servers.html#use-a-default-from-email-address

Both config params mail.force.smtp.from, mail.dynamic.smtp.from can be used to provide/override the outbound sender (From) address.

When obtaining and setup according to the documentation (links above), the outbound mails still result in error which the (documented) feature solved in version 14 and 13.

(example mail addresses non real-world):

SMTPRecipientsRefused: {'recipient@example.dev': (553, b'5.7.1 <sender@example.com>: Sender address rejected: not owned by user outbound@MTA-MAIL-PROVIDER.TLD')}

The implementation (code) exists in version 14, but not in version 15 and 16 (just search the params).
See code in version 14 (which doesn't exist in 15, 16):

• Model: ir.mail_server
• Function: _get_email_from

Currently: https://github.com/odoo/odoo/blob/14.0/odoo/addons/base/models/ir_mail_server.py#L356