occ backup:point:comment only works with comments not having blanks

I tried to set some comments at the restoring points, but it only works when replacing all blanks with _, e.g. "this_is_a_comment".
And yes, it's clear to use quotes when having blanks in CLI.
But looking at the exception trace it doesn't seem to be a backup app problem.

# occ backup:point:comment _pointId_redacted_ "this is a comment" -vvv

In ArgvInput.php line 172:
                                                                         
  [Symfony\Component\Console\Exception\RuntimeException]                 
  Too many arguments, expected arguments "command" "pointId" "comment".  
                                                                         

Exception trace:
  at /config/www/nextcloud/3rdparty/symfony/console/Input/ArgvInput.php:172
 Symfony\Component\Console\Input\ArgvInput->parseArgument() at /config/www/nextcloud/3rdparty/symfony/console/Input/ArgvInput.php:83
 Symfony\Component\Console\Input\ArgvInput->parse() at /config/www/nextcloud/3rdparty/symfony/console/Input/Input.php:55
 Symfony\Component\Console\Input\Input->bind() at /config/www/nextcloud/3rdparty/symfony/console/Command/Command.php:214
 Symfony\Component\Console\Command\Command->run() at /config/www/nextcloud/core/Command/Base.php:168
 OC\Core\Command\Base->run() at /config/www/nextcloud/3rdparty/symfony/console/Application.php:1009
 Symfony\Component\Console\Application->doRunCommand() at /config/www/nextcloud/3rdparty/symfony/console/Application.php:273
 Symfony\Component\Console\Application->doRun() at /config/www/nextcloud/3rdparty/symfony/console/Application.php:149
 Symfony\Component\Console\Application->run() at /config/www/nextcloud/lib/private/Console/Application.php:211
 OC\Console\Application->run() at /config/www/nextcloud/console.php:99
 require_once() at /config/www/nextcloud/occ:11

backup:point:comment [--output [OUTPUT]] [--remote REMOTE] [--external EXTERNAL] [--all-storages] [--] <pointId> <comment>

nextcloud: 23.0.2.1
backup:1.0.4

Reproduce the command using the quoted comment, then trace argument parsing from 3rdparty/symfony/console/Input/ArgvInput.php through core/Command/Base.php and the backup command entry point. Compare the documented backup:point:comment arguments with the observed parsing behavior. Done means a comment containing spaces is accepted as one comment argument.