Building React apps is a breeze: Once you get the hang, you'll love it. And the speed is not only a developer experience, its efficiency lowers costs and makes project management easier. Yireo has adopted React entirely and is actively running projects with it.
Yireo is also one of the forces between a subculture in the Magento ecosystem, trying to add React components to the old Magento 2 frontend. This includes a React replacement of the minicart, small UiComponents based on React and an yet-to-be-unveiled React-based checkout. Main reasons for running these experiments is to decrease development time and increase site performance. Stay tuned because we have plenty of plans here.
While it is possible to use PWA Studio, DEITY or FrontCommerce to connect your React app to Magento, you can also build it yourself. As an experiment, our main man Jisse started coding a React shop using only generic non-Magento-specific tools (React, Redux, Apollo Client) to connect to the Magento GraphQL API. The result is an educational playground (complete with routing, add-to-cart, CMS content, customer pages, login, messages and much more) that is used during training, but also as the base point for actual realizations (at least three third-parties are using its foundation and logic).
In 2018, we organized Reacticon twice: A Magento developer conference focused on PWA technology with between 120 and 210 visitors. Besides being a great conference, it was also Yireo playing a vital role in discussions on extensibility (ExtDN), standardization (GraphQL types, UPWARDS) and the general adoptation of React and Vue by the Magento community.