Cannot update to 3.x

You need to require both new versions at the same time:
composer require drupal/metatag:^2 drupal/schema_metatag:^3

Great, thanks @DamienMcKenna → ,

Another trick under the belt!

Automatically closed - issue fixed for 2 weeks with no activity.

thanks @DamienMcKenna

Hello good people, I'm trying the solution provided by @DamienMcKenna
but I'm getting

Installation failed, reverting ./composer.json and ./composer.lock to their original content.
composer [require drupal/metatag:^2 drupal/schema_metatag:^3] failed, composer command failed: exit status 2. stderr=

Running on Drupal 9.5.5

Try adding the "-v" flag to the command to get more details on what happened.

Per my understanding, PHP version it's correct. I'm running the project on ddev

Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Root composer.json requires drupal/metatag ^2 -> satisfiable by drupal/metatag[2.0.0-rc1, 2.0.0-rc2, 2.0.0, 2.0.x-dev].
    - drupal/metatag[2.0.0-rc1, 2.0.0-rc2, 2.0.0, 2.0.x-dev] require php >=8.0 -> your php version (7.4; overridden via config.platform, actual: 8.0.28) does not satisfy that requirement.
  Problem 2
    - Root composer.json requires drupal/schema_metatag ^3 -> satisfiable by drupal/schema_metatag[3.0.0, 3.0.1, 3.0.x-dev].
    - drupal/schema_metatag[3.0.0, 3.0.1, 3.0.x-dev] require php >=8.0 -> your php version (7.4; overridden via config.platform, actual: 8.0.28) does not satisfy that requirement.


Installation failed, reverting ./composer.json and ./composer.lock to their original content.
composer [require drupal/metatag:^2 drupal/schema_metatag:^3 -v -W] failed, composer command failed: exit status 2. stderr=

Yes, Metatag 2 requires PHP 8.0, so you'll have to update your ddev configuration, composer.json and server.

I added a note to the Metatag 2.0.0 release notes that it requires PHP 8.0.

Thanks @damienmckenna, so you are saying that haven't PHP version updated on ddev only it's not enough, right, I should check for PHP required version on composer.json

You need to check them all - you won't be able to use Composer if the local PHP is running PHP 7, you won't be able to update the codebase if composer.json is locked at PHP 7, you'll have problems running the codebase in ddev if it isn't running PHP 8.0, and you won't be able to deploy the changes to the production server(s) if it/they also aren't on PHP 8.