The problem with using react-testing-library with Jasmine or other alternatives is that react-testing-library renders components closely to how they would behave in a browser. Unlike Enzyme, react-testing-library doesn't provide functionality for isolated and fine-grained tests like shallow rendering and accessing component internals like props.
It's expected that all components that shouldn't be rendered as is should be mocked (here's Jest example), react-testing-library doesn't provide any functionality for it, a way they are mocked are at the discretion of a developer. Jasmine doesn't provide ways to mock modules and requires to use third-party solutions like rewire. Jest provides the functionality for module mocking, including babel-jest transform to hoist module mocks when they are used with import.
react-testing-library uses DOM. It's expected that JSDOM should be used if a test runs in Node. Jest natively sets up JSDOM, while a developer needs to set it up manually with Jasmine. It's preferable to run tests in Node rather than in a browser because this way modules can be dynamically mocked due to how Node require works.
react-testing-libraryis just a DOM testing framework and it's decoupled fromjestor any other framework. The examples showjestbecause it's what the majority of the React community uses.