Pure coding vs Wordpress

I’ve been searching for freelance jobs online, but I’ve noticed that most job posts require knowledge of WordPress, which I currently don’t have.

I’m more familiar with pure coding (React.js, Node.js, etc.), and I’m wondering — aside from the CMS (Content Management System) that WordPress offers, what’s the big advantage of using WordPress over building a website from scratch with pure code?

I’m curious why so many businesses prefer WordPress instead of opting for custom-coded websites. Is it purely for convenience, or am I missing something major? 🤔