Thank you for the bug report!

I believe on master this is fixed already:

$ project_id="$( openstack project show "$OS_PROJECT_NAME" | awk '/ id / { print $4 }' )"                                                                                                        
$ default_sg_id="$( neutron security-group-list --tenant-id "$project_id" | awk '/ default / { print $2 }' )"                                                                                     
neutron CLI is deprecated and will be removed in the Z cycle. Use openstack CLI instead.
$ openstack security group rule create --description "test rule" --remote-ip 0.0.0.0/0 --ingress $default_sg_id                                                                                  +-------------------------+--------------------------------------+
| Field                   | Value                                |
+-------------------------+--------------------------------------+
| created_at              | 2021-10-01T12:44:31Z                 |
| description             | test rule                            |
| direction               | ingress                              |
| ether_type              | IPv4                                 |
| id                      | 2025c3ff-7e5c-45df-9570-79c6a975d2fc |
| name                    | None                                 |
| port_range_max          | None                                 |
| port_range_min          | None                                 |
| project_id              | 60ff14d073834c05b8f02d1d219977a0     |
| protocol                | None                                 |
| remote_address_group_id | None                                 |
| remote_group_id         | None                                 |
| remote_ip_prefix        | 0.0.0.0/0                            |
| revision_number         | 0                                    |
| security_group_id       | 1dc8dd93-9809-411d-882b-3577f68a52a1 |
| tags                    | []                                   |
| updated_at              | 2021-10-01T12:44:31Z                 |
+-------------------------+--------------------------------------+
$ openstack security group rule show 2025c3ff-7e5c-45df-9570-79c6a975d2fc
+-------------------------+--------------------------------------+
| Field                   | Value                                |
+-------------------------+--------------------------------------+
| created_at              | 2021-10-01T12:44:31Z                 |
| description             | test rule                            |
| direction               | ingress                              |
| ether_type              | IPv4                                 |
| id                      | 2025c3ff-7e5c-45df-9570-79c6a975d2fc |
| name                    | None                                 |
| port_range_max          | None                                 |
| port_range_min          | None                                 |
| project_id              | 60ff14d073834c05b8f02d1d219977a0     |
| protocol                | None                                 |
| remote_address_group_id | None                                 |
| remote_group_id         | None                                 |
| remote_ip_prefix        | 0.0.0.0/0                            |
| revision_number         | 0                                    |
| security_group_id       | 1dc8dd93-9809-411d-882b-3577f68a52a1 |
| tags                    | []                                   |
| updated_at              | 2021-10-01T12:44:31Z                 |
+-------------------------+--------------------------------------+

Thid bug may easily be a duplicate of this:
https://bugs.launchpad.net/neutron/+bug/1904188

fixed here:
https://review.opendev.org/c/openstack/neutron/+/762692