Ocramius plugin skipped with Composer 2

Problem/Motivation

If you install a module with Composer 2 (2.0.0-RC2) you get this warning twice:

The "ocramius/package-versions" plugin was skipped because it requires a Plugin API version ("^1.0.0") that does not match your Composer installation ("2.0.0"). You may need to run composer update with the "--no-plugins" option.

Steps to reproduce

1. Switch to Composer 2.0.0-RC2 by running composer self-update --preview
2. Add a module:

$ composer require drupal/admin_toolbar
The "ocramius/package-versions" plugin was skipped because it requires a Plugin API version ("^1.0.0") that does not match your Composer installation ("2.0.0"). You may need to run composer update with the "--no-plugins" option.
Using version ^2.4 for drupal/admin_toolbar
./composer.json has been updated
The "ocramius/package-versions" plugin was skipped because it requires a Plugin API version ("^1.0.0") that does not match your Composer installation ("2.0.0"). You may need to run composer update with the "--no-plugins" option.
Running composer update drupal/admin_toolbar
Loading composer repositories with package information
Updating dependencies
Lock file operations: 1 install, 0 updates, 0 removals
  - Locking drupal/admin_toolbar (2.4.0)
Writing lock file
Installing dependencies from lock file (including require-dev)
Package operations: 1 install, 0 updates, 0 removals
  - Installing drupal/admin_toolbar (2.4.0): Extracting archive
Package container-interop/container-interop is abandoned, you should avoid using it. Use psr/container instead.
Generating autoload files
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