First, Rails is not intended for toy-app. You can build it but RoR is production ready apps. So the stack you get reflect that.
Also, you can drop like half of those gems if you do not need them.
And finaly, if you are going to do any non-trivial app in PHP you will either reinvent similar libs yourself, or you will use Symfony, Laravel, etc. and get a comparable bunch of dependencies with Composer.