The technical merits of React are hard to challenge. It has sparked a revolution in how developers build web user interfaces - with or without React. Facebook's somewhat unclear licensing (BSD+Patents) have been fuel for FUD among Open Source developers. FOSS communities continue to have a built in resistance to "evil corporations", to which Facebook can easily be classified to.
Many web developers recall working with Sharepoint as a web CMS as a horrible tool. Customization the table structures generated by the proprietary backend code was the antithesis in the heydays of the web standard movement in the 2000's.
During 2016 some of the risks that security experts have warned regarding the IoT (Internet of Things) have realised.
Ghost is a blogging platform written in Node.js. It is fairly popular and a direct competitor to WordPress. Ghost also has a pleasing aesthetic.
So much so, that WordPress.com, a commercial entity, decided to take their default theme and use it. Without permission and explicitly breaking the licensing terms. OMG, evil corporation taking advantage of the organic artisan developer!
YouTube is the undisputed video platform for the web. Back in 2005 when it launched it revolutionized online video with Flash (yes, that Flash) and was acquired by Google in October 2006.
Casual video viewers as well as amateur and professional content creators, everybody uses YouTube. From Flash to HTML5 video the technology has evolved. Now YouTube going for Web Components.
Angular, React and Vue.js are three popular technologies that are widely deployed and used for creating rich user interfaces for web applications. They're all somewhat of competitors, but at the end of the day they are all comparable and none holds a significant advantage.