Is that worth the fact that for each request its service provider is called and the class map gets bigger with it and its dependencies?

Maybe, the service provider can only be called when needed. That's the actual problem here.

It has autodiscovery in its composer.json so you would need to manually register it on local and alter its composer.json to register it manually.

Anyway thank you. From my point of view it belongs to require-dev and it can be moved there in each project (template).

I looked in the composer.json of this repo (the framework) and it is shown only as a suggestion and not a require. So which template exactly?

This repo is the kernel not the template that requires it.

https://github.com/laravel/laravel/blob/ad4ca3e9a02ed4104f8a42657219fdbe199462eb/composer.json#L11

Why not make a Pull Request to move it to require-dev?

Because I did that for my own project without the risk of upseting anyone by doing so :).

You know that the power of defaults is big.