I just ran into the same issue on 10.1 so this needs to be reopen, however Comment#25 worked for me.
Following the description for "installation on existing site" (composer require "drupal/commerce"), I got the following error:
===
Your requirements could not be resolved to an installable set of packages.
Problem 1
- Installation request for drupal/commerce ^2.23 -> satisfiable by drupal/commerce[2.23.0].
- drupal/commerce 2.23.0 requires drupal/inline_entity_form ^1.0-rc6 -> satisfiable by drupal/inline_entity_form[1.x-dev, 1.0.0-rc6, 1.0.0-rc7, 1.0.0-rc8] but these conflict with your requirements or minimum-stability.
A similar error appear when installing the dev version.
Fixed
2.0
Commerce
Not all content is available!
It's likely this issue predates Contrib.social: some issue and comment data are missing.
I just ran into the same issue on 10.1 so this needs to be reopen, however Comment#25 worked for me.