Plugins and themes. WP integrates with everything and has enough over the shelf for 70% of companies to run their blogs/sites. The enterprise offering also allows for complete customization, which is why we see so many large organizations still on the platform (they are also somewhat resistant to changes, but that's another topic
The alternatives, like Sanity, Contentful, and Webflow are either too simplistic or too robust to answer to the needs to most companies.