The reason of it:
you should never use the symfony/symfony package. Since a long time now, individual components should be used instead, we "only" keep symfony/symfony as a mono-repo where development happens (and for BC reasons, but we might remove the package from Packagist at some point).

e.g. conflicts:

• https://github.com/symfony/symfony/blob/5.4/.gitattributes#L4
• dist is different from source for symfony/symfony. So actually https://github.com/symfony/symfony/archive/refs/tags/v5.3.0.zip is different from what you see here https://github.com/symfony/symfony/tree/v5.3.0