Too Long; Didn't Read
Selenium is the most popular web UI automation tool in test automation market. WebdriverIO is available for JavaScript (TypeScript) only, while most of the test automation projects are being developed using Java, Python and etc. Selenium uses webdriver to interact with browser, while there's much faster DevTools protocol (but it doesn't support many browsers at current moment). Not many companies perform cross-browser testing, they just run their tests on Chrome and that's it. Selenium can do the same things that Selenium, but also comes with lots of integrations with popular test automation tools out of a box.