When did plugins start to require a paid "plan"?

Create a free website or build a blog with ease on WordPress.com. Dozens of free, customizable, mobile-ready designs and themes. Free hosting and support.

As others have already said, you're describing wordpress.com which isn't what you want. That's a hosting service (owned by Automattic) that provides a severely locked down version of WordPress whereby you need to pay for certain plans to gain access to things like plugins.

Provides a simple, local development environment with a friendly GUI.

If you want to play around with WordPress you can download something like LocalWP to set up a local version of WordPress on your own computer. You can mess around, develop etc... There if you wanted :).